Does anyone here know about the immigration ticket which is required at check in at Conrad Bangkok. I was told the airline will give it at check in counter before boarding . We are US citizen and will fly to Bangkok with ANA . I contact ANA and the airline representative does not know what I am talking about. So far, from what I read online that only the proof of vaccine is required and passport must be valid for at least 6 months. Am I missing something or the rule to enter bangkok is changed again.

Please advise and thank you.