Recently I'm having issues using Skype to place calls to 800 numbers.
On computer, phone and tablet they are not connecting or going through.

Is anyone else having this problem?

All devices updated.
Skype updated on everything.
Since this is happening on all my devices using my WiFi I'm wondering what to do, what to check. 

I did try using AIS WiFi, but didn't work either.  I'll try a few other locations.
 

Any constructive help on this is most appreciated.  I'm stumped.  

Wed-Sat I placed at least 10 calls to an 800 number in the US. No issues. Just tried again before posting this and again call went right through.

I just called a 800 number and it rang until I got a message to call later.

I am using True Online fibre.

Thank you, that was helpful in letting me know it wasn't a Skype problem.  
........

For the record - in case someone else runs into this problem this might be helpful.
 

After checking every possible setting on the phone, tablet, computer and checking the WiFi settings I'm pretty sure I found the culprit.
In Skype>settings>calling>caller ID> it was ON.  I'm thinking I had turned it on a while back when registering a website or verify something.
So
Turned caller ID off, tried 3 numbers, it worked.
Turned it back on (I like to test out things to make sure...555) called same numbers wouldn't work.  Ok, this is the problem.
Turned called ID off, tried the 3 numbers it didn't work... damn.
Turned tablet off, back on, called the numbers and it works... so does the phone and computer.
 

I'm thinking Skype was seeing it was coming from a Thai phone number ?? (not sure why that affected the tablet/computer).
 
I want to confirm you are using the Free version/service of calling Toll Free numbers abroad.

IF you would, please check to see if your Caller ID is OFF or ON.