Originally Posted by Thai-Kiwi

It should be possible to change your seats, although the location where you do this is a bit obscure. I assume you have the THAI booking reference.

Go to ‘My Booking’ and enter information and select ‘Find Booking’. This will bring up the specific reservation.

Now scroll down to a dark banner titles ‘Services’, and click on ‘additional services’. This brings up the page that has additional baggage, seat selection, special meals.

Click ‘Select you Seat’ which opens a pop-up window where you can make selections. You must click ‘confirm and close’ to save the changes made.

Easy!!

Originally Posted by Global321

Thai-Kiwi gave you good advice.

If for any reason you cannot do it online, try a DM tweet. If that does not work, try a Skype call to Thailand. It will be pennies per minute.