I cannot purchase apps and verify credits card on iPad

[I'm Apple user form Thailand Sorry for my English grammar]

Cause : I cannot purchase any apps and verify credits card on iPad Air but I can do both things on iPhone with the same Apple ID

I already send my problem to iTunes support and they reply me that " Your account is not in compliance with the iTunes Store Terms and Conditions. Please note that you will still be able to play, authorize, and sync all of the items that were purchased using this account "

After that I read iTunes Store Terms and Conditions. I don't know which conditions that my ID do not compliance with.

I still have that problem now. and I don't have ant idea what should I do to troubleshooting that

Thanks for helping me