Matt AA

I work at AA Insurance Brokers and we offer CORIS also. That is when it comes available again as CORIS has a temporary stop on new clients for the annual policies.
CORIS does not have a branch on Koh Samui. The Koh Samui office is a broker just like AA, they only opted to present themselves as being CORIS. 

The plan of CORIS is really a travel insurance. 
I now quote form the information we send to potential clients:
 

There is no Medical Questionnaire as a part of the application so Coris will investigate the medical history in case of doubts.

• Any pre-existing conditions and/or medical conditions like diabetes, heart conditions, high blood pressure etc. will be excluded from coverage unless it will be classified as “Acute deterioration of chronic illnesses”.
• The Coris plans are more a travel insurance then a Health Insurance. Among other things this means no automatic renewal. Renewal can be refused when the policy year ends.
• There is NO coverage for COVID-19.
• The Insurance policy will enter into force 8 days after Coris receives the payment.
• There is NO coverage in your Country of Origin.
• When applying over the age of 75, the Premium will increase with 50 %, when older than 85 it will be double (100 % extra).  

As mentioned above this is not a regular Health Insurance. To avoid all misunderstandings some more explanation about the coverage:
If you are sick or got injured you have to see a doctor so that is urgent. Coris covers a doctor visit, medicines, operation, hospitalization, follow up etc.
However, after you had an urgent medical treatment and the doctor afterwards says it might be good for you to take additional tests or physiotherapies or something similar, this follow up will no longer be covered. If Coris does not know what is wrong with you, Coris will not pay for any “research” of what so ever.
Another very important thing: If you have a major injury or severe disease, Coris will only cover medical costs until you are fit enough to be transported to your homeland. In case somebody lives in Thailand it will make no sense for him to return to for example Russia (as he has no health insurance and no residence there anymore) – at that moment the coverage by Coris stops.

With this regards we specifically want to use this quote from Coris:

“What I want is to be very clear to all your clients that pre-existing medical conditions are not covered and that we only cover urgent medical issues. If someone gets seriously ill we are not going to pay for a long term treatment but instead such person is taken to his homeland. If the client doesn’t want that, the coverage stops at that point.”

A real health insurance is of course much better as it will also cover for not urgent medical issues. Having said that, a real Health Insurance has a price, especially when getting older, so the CORIS option is still a good one for everybody that does not have the means to go for a real health insurance. As long as you keep in mind it has its limitations. 

Cigna normally will cover for a private room if the Hospitals only have private rooms. 
I refer to Cigna Scotland here with i.e. the Close Care plan, Silver plan etc. (as Cigna also recently started offering Thailand based plans).

You can extend your present AXA insurance.

You can contact www.aainsure.net. AA works with all Thai Companies and a few offer the possibility to apply when over 70. 

www.aainsure.net works with all companies so it is easy to compare. Multiple offices in Thailand, specialized in Health Insurance. 

Be careful because in the plans that cover for a semi-private room, you will have to pay 20 % of the total bill by yourself in case you do stay in a private room. Not only for the room price but the total bill. This can be an issue since most private hospitals in Thailand only have private rooms. If you wish to receive more information, just drop an e-mail at www.aainsure.net.
 

I think it is very difficult for anybody to give you assistance with this limited information. It really depends on the kind of policy you have and especially the general conditions. I can only say that it does not sound very weird. A lot of travel insurers only cover for medical emergencies so maybe that is the reason why the investigations are not covered.... 

Best to contact www.aainsure.net. As a broker AA can offer home insurance plans of many different companies so it is easy to compare. 

You can contact www.aainsure.net. 
As a Broker we work with all Thai Companies which makes it easy to compare. 
Multiple offices in Thailand, specialized in Health Insurance.