Im gettin new passport europe to here... and i have now extend stamp my passport... next i have to extend by c-19... do i have to carry that new passport with me all the time ? And can they stamp that extend to my new passport ? do i get some trouble in there or something? (if they see my passport not valid anymore, but i still have my new passport with me).. thanks
TLDR : Answer Summary
When you get a new passport while in Thailand, you should carry both your old and new passports to the Immigration office. The stamps from your old passport can be transferred to your new passport. It is important to have a valid passport with you at all times in Thailand.