Dual citizenship - my visa is running out soon! Help

[skatewash]

Where is the problem?

You simply stamp out at the thai side, change passports and take the queue to enter Thailand.

You don't have to enter Cambodia.

If a officer ask you what you are doing you simply tell him the truth.

You changed passports because you don't want to become a overstayer in your own home country.

Here's the problem. What if the immigration officer says no? Even after the explanation from the OP. What if he says, "no you can't do it that way?" What if he says, "the best I can do for you is to let you come back in on the Swedish passport?" In that case it seems like a wasted trip to me. The outcome is in the hands of the immigration officer, and unfortunately not in the hands of the OP.

mgb is absolutely right. She cannot be denied entry.

Entering Cambodia isn't necessary if she is using her Thai passport to enter Thailand and the Thai passport doesn't have an exit stamp.

If she can enter Cambodia with the Thai passport then great. If she can't then whats the point in entering Cambodia when she can just cross the road?

Do you personally know anyone who has done what you advise doing?

[elviajero]

Ok guys. I just spoke with the Immigration Office for 51 mins, here's what he said;

I can only get a 1 year extension, if my employer can give me some kind of letter to the Immigration, saying that I wish to stay and work in Thailand.

I can change my Non-B Visa into a Non-O, if I go to any Thai Embassy outside Thailand, then come back with my Swedish Passport that they've changed to Non-O, stay for another 90 days, then after that they can extend for another year.

I am not employed any longer, so that can't happen. I can go with option 2, but it will take more time and money for me to do so.

I can fly or go by land to any neighbor country, stamp out with my Swedish passport - MIGHT get a problem with Cambodia Immigration when I enter with my Thai passport because they won't see an exit stamp. But if I enter with my Swedish Passport I won't get a problem, but then when I want to enter Thailand again with my Thai Passport, I MIGHT get a problem with the Thai Immigration because they won't see an enter/exit stamp from Cambodia. IO told me that it MIGHT happen that they ask, but as far as I could understand, I'll just have to explain or show my two passport, if it comes to that. But there's no issue going by land! Same as going by air he said. Whatever is more convenient for me.

IO also told me that, if I do the extension, Immigration will probably ask me what passport I would like to use (as Thailand IO are not to keen on dual), if I then choose Thai passport, then my Swedish passport will be IINVALID!!

Extension.

The IO is right if the reason for the extension is for work BUT you are Thai and I believe you qualify for an extension of stay as a Thai regaining her nationality.

The immigration police order outlines the criteria and conditions for extensions.

2.23 In the case of a person who used to have Thai nationality or whose parent is or was of Thai nationality visiting relatives or returning to his or her original homeland:

Each permission shall be granted for no more than one year.

Land or Air

The problem of not having an exit stamp can still come up even if you fly out and back in. An IO at the airport could also insist you use you Swedish passport.

The only way you can guarantee not to have this problem is to fly out and re-enter using the automatic gates.

If you decide to give your land border plan a go, My advice would be.......

When you exit Thailand fill out the departure card for your Swedish passport AND fill out a departure card for you Thai passport too. Give both passports to the Thai IO and ask him to stamp exits in both. He may or may not do this but It's been done before and is possible. If he stamps your Thai passport then your problems are solved.

If he doesn't then try and enter Cambodia with the Thai passport. If successful then again the problem is solved.

If you have to enter and exit Cambodia with the Swedish passport then when you enter Thailand hand them only your Thai passport. If they query no exit stamp then explain the situation and ask as politely as possible that the IO uses your Thai passport.

If the Thai IO insists on the Swedish passport and the plan fails you'll get a 15 days which can be extended at the least for 30 days but should be possible for 1 year.

Dual Nationality.

You are legally entitled to dual nationality and no immigration officer can make you choose or cancel either of your passports.

[nem0z]

skatewash: I can see what you're trying to tell me, and I've thought about it myself the whole morning after the phone call to Immigration Office. I'm very skeptic about this whole thing, but I'm expecting problems at the border for sure. Luck has never been really existed in my life. And as you say, it will get very stressful being in a discussion with the Immigration Officers at the border when I'm not really fluent in Thai, trying to convince them that I'm right and to let me pass. But spending 400 baht ish to the border to at least try, seems OK. But if they now refuse my entry with my Thai passport and I have to enter with my Swedish, how long will I get in Thailand? 15 more days?

I really like your advice and I'm considering really hard to go by air. Seems hassle-free and much easier than going by land.

Since I arrived in Thailand 3 months ago, nothing has been easy so far. I kinda just want to get this over with as soon as possible, so I can start looking for a job and not to worry about anything for once!

I'll think hard today, and make up my mind on how to do this. If I had plenty of money, I wouldn't hesitate taking a flight over to Cambodia. But as I'm running low on cash, I need to plan this carefully.

[nem0z]

The IO told me that I could extend my visa for a year, because I have family here in Thailand. But it would still require me to go to a Thai Embassy in another country to change my Non-B visa into a Non-O in my Swedish passport.

By using the automatic gate, I understand.

Ok, if I go, I'll do that. Two departure cards, got it.

"Dual Nationality.

You are legally entitled to dual nationality and no immigration officer can make you choose or cancel either of your passports."

Thank you! I really didn't want to believe the IO telling me I had to give up my Swedish passport. What a relief!

Edited August 31, 2015 by nem0z

[elviajero]

Where is the problem?

You simply stamp out at the thai side, change passports and take the queue to enter Thailand.

You don't have to enter Cambodia.

If a officer ask you what you are doing you simply tell him the truth.

You changed passports because you don't want to become a overstayer in your own home country.

Here's the problem. What if the immigration officer says no? Even after the explanation from the OP. What if he says, "no you can't do it that way?" What if he says, "the best I can do for you is to let you come back in on the Swedish passport?" In that case it seems like a wasted trip to me. The outcome is in the hands of the immigration officer, and unfortunately not in the hands of the OP.

mgb is absolutely right. She cannot be denied entry.

Entering Cambodia isn't necessary if she is using her Thai passport to enter Thailand and the Thai passport doesn't have an exit stamp.

If she can enter Cambodia with the Thai passport then great. If she can't then whats the point in entering Cambodia when she can just cross the road?

Do you personally know anyone who has done what you advise doing?

No. And I'm not advising she do that.

If she enters and exists Cambodia using her Swedish passport she will be handing over a blank Thai passport. mgb's point is that why does she need to enter Cambodia for what would be a pointless exercise when Thai immigration have to, by law, let her in whether or not she entered Cambodia.

[skatewash]

skatewash: I can see what you're trying to tell me, and I've thought about it myself the whole morning after the phone call to Immigration Office. I'm very skeptic about this whole thing, but I'm expecting problems at the border for sure. Luck has never been really existed in my life. And as you say, it will get very stressful being in a discussion with the Immigration Officers at the border when I'm not really fluent in Thai, trying to convince them that I'm right and to let me pass. But spending 400 baht ish to the border to at least try, seems OK. But if they now refuse my entry with my Thai passport and I have to enter with my Swedish, how long will I get in Thailand? 15 more days?

I really like your advice and I'm considering really hard to go by air. Seems hassle-free and much easier than going by land.

Since I arrived in Thailand 3 months ago, nothing has been easy so far. I kinda just want to get this over with as soon as possible, so I can start looking for a job and not to worry about anything for once!

I'll think hard today, and make up my mind on how to do this. If I had plenty of money, I wouldn't hesitate taking a flight over to Cambodia. But as I'm running low on cash, I need to plan this carefully.

I see your point. If you approach it with the attitude you have: that it may or may not work but it's at least worth a shot to find out, then I think you'll be fine. I didn't want you to think it was a certainty to work as you might think based on some of the other responses, that's all. Best case, it will work as you wish and you will have saved some money. Worst case, you should at least end up with 15 more days, and perhaps, an interesting story to tell. Being a charming Thai woman certainly shouldn't hurt your case ;-) I wish you the best of luck.

Edited August 31, 2015 by skatewash

[nem0z]

skatewash: I can see what you're trying to tell me, and I've thought about it myself the whole morning after the phone call to Immigration Office. I'm very skeptic about this whole thing, but I'm expecting problems at the border for sure. Luck has never been really existed in my life. And as you say, it will get very stressful being in a discussion with the Immigration Officers at the border when I'm not really fluent in Thai, trying to convince them that I'm right and to let me pass. But spending 400 baht ish to the border to at least try, seems OK. But if they now refuse my entry with my Thai passport and I have to enter with my Swedish, how long will I get in Thailand? 15 more days?

I really like your advice and I'm considering really hard to go by air. Seems hassle-free and much easier than going by land.

Since I arrived in Thailand 3 months ago, nothing has been easy so far. I kinda just want to get this over with as soon as possible, so I can start looking for a job and not to worry about anything for once!

I'll think hard today, and make up my mind on how to do this. If I had plenty of money, I wouldn't hesitate taking a flight over to Cambodia. But as I'm running low on cash, I need to plan this carefully.

I see your point. If you approach it with the attitude you have: that it may or may not work but it's at least worth a shot to find out, then I think you'll be fine. I didn't want you to think it was a certainty to work as you might think based on some of the other responses, that's all. Best case, it will work as you wish and you will have saved some money. Worst case, you should at least end up with 15 more days, and perhaps, an interesting story to tell. Being a charming Thai girl certainly shouldn't hurt your case ;-) I wish you the best of luck.

If it doesn't work out, and I come back with my Swedish passport and given 15 more days, I can at least take it a little slower and find a date before my 15 days expire to fly out, use the automatic gates using my Thai passport. And all shall be well, right?

Charming huh .. If I was, I would probably still have my job here in BKK and probably also have a boyfriend haha

Thank you for taking time to write me back on my silly questions, all of you! You guys have no idea how calm you've made me.

[elviajero]

The IO told me that I could extend my visa for a year, because I have family here in Thailand. But it would still require me to go to a Thai Embassy in another country to change my Non-B visa into a Non-O in my Swedish passport.

I don't have any personal experience so I'm cautious in giving advice.

Again, the IO is correct. You could apply for an extension due to family but thats meant primarily for 100% foreigners. You are Thai and as such qualify for an extension for being Thai that a 100% foreigner can't get.

So you have another choice/option. And as far as I know (and theres nothing in the rule book) it doesn't matter what visa you have if you apply for an extension of stay for the reason of being a Thai citizen.

[nem0z]

Had another go with the Immigration Office. They told me same thing about the extension. So no luck there.

And this person told I had to leave by air only. So I guess I'll be doing that then ...

Just to solve this problem and move on!

/Nemo

[nowretired]

Had another go with the Immigration Office. They told me same thing about the extension. So no luck there.

And this person told I had to leave by air only. So I guess I'll be doing that then ...

Just to solve this problem and move on!

/Nemo

Have actually been to the immigration office ?

[chatette]

There is an enormous amount of misinformation on this thread.

You do not have to do ANYTHING.

You are a Thai citizen and can not overstay.

The visa in your Swedish passport is now irrelevant and superseded by your status as a Thai.

From now on, you exit and enter Thailand using only your Thai passport.

You can use your Swedish or Thai passport to enter and exit whatever other countries you choose, with the exception of Sweden where you would use your Swedish passport.

It's that simple.

I have personal experience of this as I have been in exactly the same situation.

[nowretired]

There is an enormous amount of misinformation on this thread.

You do not have to do ANYTHING.

You are a Thai citizen and can not overstay.

The visa in your Swedish passport is now irrelevant and superseded by your status as a Thai.

From now on, you exit and enter Thailand using only your Thai passport.

You can use your Swedish or Thai passport to enter and exit whatever other countries you choose, with the exception of Sweden where you would use your Swedish passport.

It's that simple.

I have personal experience of this as I have been in exactly the same situation.

If there is "misinformation" on this thread you have just added to it.

Departing Thailand requires that the same passport used to gain entry is used.

[elviajero]

There is an enormous amount of misinformation on this thread.

You do not have to do ANYTHING.

You are a Thai citizen and can not overstay.

The visa in your Swedish passport is now irrelevant and superseded by your status as a Thai.

From now on, you exit and enter Thailand using only your Thai passport.

You can use your Swedish or Thai passport to enter and exit whatever other countries you choose, with the exception of Sweden where you would use your Swedish passport.

It's that simple.

I have personal experience of this as I have been in exactly the same situation.

You are right. Legally they can't charge an overstay fee to a Thai citizen and as long as she never uses her Swedish passport to enter or exit Thailand she shouldn't have a problem. But unless she exits with the Swedish passport she will get in to a technical overstay. If she then ever wants to exit/enter with that passport (don't know why she would) then she might have a difficult conversation with an IO.

Although legally IO's can't fine a Thai for overstay they do.

The OP has asked for help to get here passports in order. "Enormous amount of misinformation" is an enormous exaggeration!

[skatewash]

Had another go with the Immigration Office. They told me same thing about the extension. So no luck there.

And this person told I had to leave by air only. So I guess I'll be doing that then ...

Just to solve this problem and move on!

/Nemo

Good. I think you've done your due diligence investigating the possibilities. My suggestion if you decide to fly-out, fly-in is to use AirAsia and Kuala Lumpur (their hub airport), but any country and any airline will do for your purposes so if you find a better deal somewhere else go for it.

I recommend you book two one-way tickets since Air Asia doesn't give a discount for a round trip and it will make your dealings with the airline at check-in easier (especially with the different last names in your passports). I also recommend using your Swedish passport to travel to Malaysia, because it's good practice for the Canada trip (just to be clear both the Swedish and Thai passport will allow you to go to Malaysia without a visa):

1a) Book ticket from Thailand to Malaysia using Swedish passport details.

1b) Book ticket from Malaysia to Thailand using Thai passport details.

2) Check-in at Thai airport using your Swedish passport.

3) Exit Thai immigration using your Swedish passport. [This is important because it will leave your Swedish passport in a good state: entered Thailand, exited, and didn't overstay.]

4) Enter Malaysia using your Swedish passport.

5) Enjoy the international terminal at Kuala Lumpur, there are worse places to spend an hour or so.

6) Check-in at Malaysian airport using your Thai passport.

7) Exit Malaysian immigration with your Swedish passport. [Again, you are leaving on the same passport you used to enter the country.]

8) Enter Thai immigration with your Thai passport. Best to use the automatic gates to save time and no possible discussion, just scan your Thai passport.

The biggest benefit to doing this is that upon your return to Thailand using you Thai passport you never have to any dealings with Thai immigration office again! Only immigration at airports and borders and then you will be a Thai citizen using a Thai passport so there should be no future problems. As a side benefit, this is a good trial run for your Canada trip. Booking something mid-week should be cheaper and look out for Promo fares which are quite a good deal. Often times the promo fares are available on early morning flights and evening flights. Oh, and make sure you allow enough time between flights, two hours minimum between landing and leaving to come back to Thailand, just to be safe. AirAsia allows online check-in up to 14 days in advance (I think), so you can do your check-in before you even begin the trip. You won't need to pay for a checked-baggage allowance, and I would decline to purchase any trip insurance on the tickets to save money.

[elviajero]

Had another go with the Immigration Office. They told me same thing about the extension. So no luck there.

And this person told I had to leave by air only. So I guess I'll be doing that then ...

Just to solve this problem and move on!

/Nemo

I still think they are wrong but they have the only opinion that counts.

[chatette]

There is an enormous amount of misinformation on this thread.

You do not have to do ANYTHING.

You are a Thai citizen and can not overstay.

The visa in your Swedish passport is now irrelevant and superseded by your status as a Thai.

From now on, you exit and enter Thailand using only your Thai passport.

You can use your Swedish or Thai passport to enter and exit whatever other countries you choose, with the exception of Sweden where you would use your Swedish passport.

It's that simple.

I have personal experience of this as I have been in exactly the same situation.

You are right. Legally they can't charge an overstay fee to a Thai citizen and as long as she never uses her Swedish passport to enter or exit Thailand she shouldn't have a problem. But unless she exits with the Swedish passport she will get in to a technical overstay. If she then ever wants to exit/enter with that passport (don't know why she would) then she might have a difficult conversation with an IO.

Although legally IO's can't fine a Thai for overstay they do.

The OP has asked for help to get here passports in order. "Enormous amount of misinformation" is an enormous exaggeration!

[chatette]

I have been in EXACTLY the same position as the OP by gaining citizenship while holding a Cat B visa in my other nationality passport.

The visa in the other nationality passport is SUPERSEDED by Thai citizenship.

You do NOT have to leave the country using your Swedish passport as you have gained Thai citizenship in the meantime.

You can not be charged overstay when exiting as you have gained Thai citizenship since your entry on a foreign passport.

You are a Thai citizen and must exit and enter Thailand using only your Thai passport.
You can not be denied entry as a Thai citizen.

Immigration officials are not involved in the citizenship process and have absolutely no idea of the process. Interior or foreign ministry officials are where you will get the information you need.

While in Thailand you have all the rights of any other Thai citizen, with the exception of the right to vote as in some circumstances you must wait 5 years.

Please PM me if you want clarity and I can refer you to high level officials who you can speak to in English personally if that helps.

[chatette]

This is the Foreign Ministry of Thailand contact you need to clarify your situation:

Department of Consular Affairs Tel: 0-2981-7171 or 0-2981-7276-7 Fax: 0-2981-7256 or by e-mail at [email protected]

http://www.mfa.go.th/main/en/services/1415/21483-Frequently-Asked-Questions-(FAQs).html

They speak English!!

[nem0z]

skatewash; Thanks again for the very detailed information given about how I should do the flight to KL. I appreciate it so much you have no idea! I would've been lost without your guidance.

I was actually looking at tickets to KL, and realized I had no clue what personal info I should fill in with, the one from my Swedish or the one from my Thai passport.

Having two different passports is sure confusing but also having two different last names is confusing as well (thanks to my mom who changed it for me when I was 15yo).

And once this is over, I'll be happy to never have to deal with Thai Immigration Office again!

And you're right, this is good practice for Canada

I'll book two one-way tickets asap.

Wish I could buy you a beer/soda/coffee as a thanks!

chatelette; I'll give them a call as soon as I can. I'm curious to know if they can tell me something differently and legit about my dual citizenship. Thank you!

[chatette]

Thx. Feel free to PM me if you have problems speaking to a knowledgable person and I'll pass you the contact for the unit head.

It's simple once you get your head around the fact that the visa is now irrelevant because you've since gained the citizenship. Enjoy life as a Thai! Much simpler!

[beerzy]

nowretired ;

Airasia seems to be the cheapest I can find, tho they fly out from Don Mueang Airport and right now I live very close to

Suvarnabhumi Airport, but Cambodia Angkor Air and Bangkok Airways are expensive or don't fly out the dates I need.

Airasia flies for 3100 baht ish.

Hi,

I see this and dont believe.

1.are you a thai or a swede?

You can get a multiple entry Non immigrant B visa. I have one. When that is about to expire I am told I can get a 12 month one where I dont have to go out every 3 months (Legal firm Sunbelt Asia). Talk to me direct for further information.

no is you are a swede, who did you geta thai passport and ID card??

Oh fly to singapore as its cheaper than the prices mentioned and its quick too. complete in one day

Edited August 31, 2015 by beerzy

[LukKrueng]

You make the switch with air travel - doing by land may be possible with officials help but it is not normal as both countries check for stamps in your passport prior to allowing entry. By air this is not an issue - the only issue will be you not having a departure card on your Thai passport (as normal travel) but you can explain your last departure was with a foreign passport (but best to keep it out of sight as some would want to use for entry if you do not stand your ground - they must allow entry to you as a Thai by law so most people have little or no problems at airport where it happens often - but at land crossing most do not understand and it can be total refusal of entry). You do not have to spend any amount of time outside of Thailand (but return flights are normally too close in time to make connection).

Thai people don;t have the departure card in their passport while in Thailand. They use the same form but in reverse - when they leave Thailand they have the arrival card in their passport till they return...

As for border run - as many ave said - you can't do it. When you enter Cambodia they'll check for the exit stamp of the Thai side and vise versa.

You said you went to the immigration office when you got your new Thai passport - how is that possible? It's 2 totally different places and authorities... You should go to the immigration office where they deal with non Thai's visas issues and ask there. However, I think you should have no problem just staying here and forget your visa in the Swedish passport. Once you got your Thai ID you are here as a Thai and that's it. Whenever you fly anywhere in the future you just use your Thai passport to leave the country. If you go to any of the 9 other ASEAN countries you use your Thai passport, and if you go anywhere use the Swedish passport to enter and exit that country.

[chatette]

Btw, names and direct line contacts of Director-General and other Consular Affairs officials are on the Web link I posted in the Directory section under Ministry of Foreign Affairs sub-head after Home on the top menu banner.

You want the Visa and Travel Documents Division. The director's name is there.

[nem0z]

LukKrueng; I got the passport from the Ministry of Foreign Affairs, and after that went to the Immigration Division, which is next door building. But they were of no help when I was there.

So when I fly out from Thailand to Canada in two months, I will not have any problem leaving the country with my Thai Passport that has a different last name than on my Swedish passport, also the one I entered the country with 3 months ago?

[Phimeow]

My 2c's worth:

For best result exit Thailand via air using your Swedish passport. This leaves your Swedish passport in a good state i.e. no overstay. You never know when your Swedish passport will come in handy when you next travel so it's best to keep everything legal.

Return to Thailand using your Thai passport - autogate works really well. Once you are in as a Thai - no more issues.

(From personal experience, I also have dual citizenship)

[chatette]

You will have absolutely no problem leaving Thailand on your Thai passport regardless that you entered on the Swedish.

Reiterating: your status in Thailand as a Swedish passport holder with a catB visa is superseded by you subsequently gaining Thai citizenship.

[nem0z]

Had another go with the Immigration Office. They told me same thing about the extension. So no luck there.

And this person told I had to leave by air only. So I guess I'll be doing that then ...

Just to solve this problem and move on!

/Nemo

Good. I think you've done your due diligence investigating the possibilities. My suggestion if you decide to fly-out, fly-in is to use AirAsia and Kuala Lumpur (their hub airport), but any country and any airline will do for your purposes so if you find a better deal somewhere else go for it.

I recommend you book two one-way tickets since Air Asia doesn't give a discount for a round trip and it will make your dealings with the airline at check-in easier (especially with the different last names in your passports). I also recommend using your Swedish passport to travel to Malaysia, because it's good practice for the Canada trip (just to be clear both the Swedish and Thai passport will allow you to go to Malaysia without a visa):

1a) Book ticket from Thailand to Malaysia using Swedish passport details.

1b) Book ticket from Malaysia to Thailand using Thai passport details.

2) Check-in at Thai airport using your Swedish passport.

3) Exit Thai immigration using your Swedish passport. [This is important because it will leave your Swedish passport in a good state: entered Thailand, exited, and didn't overstay.]

4) Enter Malaysia using your Swedish passport.

5) Enjoy the international terminal at Kuala Lumpur, there are worse places to spend an hour or so.

6) Check-in at Malaysian airport using your Thai passport.

7) Exit Malaysian immigration with your Swedish passport. [Again, you are leaving on the same passport you used to enter the country.]

8) Enter Thai immigration with your Thai passport. Best to use the automatic gates to save time and no possible discussion, just scan your Thai passport.

The biggest benefit to doing this is that upon your return to Thailand using you Thai passport you never have to any dealings with Thai immigration office again! Only immigration at airports and borders and then you will be a Thai citizen using a Thai passport so there should be no future problems. As a side benefit, this is a good trial run for your Canada trip. Booking something mid-week should be cheaper and look out for Promo fares which are quite a good deal. Often times the promo fares are available on early morning flights and evening flights. Oh, and make sure you allow enough time between flights, two hours minimum between landing and leaving to come back to Thailand, just to be safe. AirAsia allows online check-in up to 14 days in advance (I think), so you can do your check-in before you even begin the trip. You won't need to pay for a checked-baggage allowance, and I would decline to purchase any trip insurance on the tickets to save money.

For some weird reason, I can't book. I end up with an error when I try to book one one-way ticket.

Errors

• Object reference not set to an instance of an object.

Not sure what it means, but when I try again, I end up with the same error.

[nowretired]

Re load the web site and then , carefully, complete the booking .

[skatewash]

Re load the web site and then , carefully, complete the booking .

Yes, it might be a random error and trying it again might be successful.

Another thing to try is to simply use another browser if you have access to more than one browser. In other words, if you were using Chrome when you got the error, try using Internet Explorer instead. This will sometimes resolve the problem and the error will not reoccur.

It should not be a problem with just booking a one-way flight. I do that often. I did have a problem once using the Air Asia site while in Chrome and so I tried doing the same thing in Internet Explorer instead. It worked. But as I prefer Chrome I use it now to access Air Asia and haven't had the problem occur again. May have been a cookie problem, don't know and didn't investigate it as there was a good workaround at hand.

Edited August 31, 2015 by skatewash

[rocketmankabin1]

I am Thai/American. Been going in and out for years. I leave America with my American passport and come into Thailand on my Thai passport. When I leave, I show both at immigration. Because if I just showed my American, they would look for entry card and visa. If I just showed my Thai, they would look for a visa for America. Come in on a Thai passport, leave with both.

Not sure if you can get an extension. You may have to leave the country by plane. Good luck.