First name contains an invalid character

I have the same problem and contact apple support group today. Finally I resolve this problem. This is the way how I resolve it. First I go to my Apple ID account with appleid.apple.com and change my name in English in account section. Then click "done". After that I back to App Store and sigh out from my account then sign in again. Put all the information in English and put address first line with your street and second line with your unit (if your address has two lines). Then it will do not show the error message again. Hope this can help you.

I have the same problem. And it seems this problem started at this month...

I think this is a bug with beta? Are you guys all on beta as well? Thanks for this post the solution worked for me as well. I don't know if it's either due to the fact we're using non-english names associated with the account, or if you guys are on beta as well. Either way the solution worked for me as well.

Steps:

• Go to https://appleid.apple.com/ and sign in
• Change your name to something else just temporarily.
• Go back to your device and sign out of the apple account.
• Sign back into the apple account, and then re-enter the payment details and correct your name.
• The account should work normally then! Thanks for the OP for clearing this up!

same problem, cost me all day to try to find the way, finally finding it here, thank you very much!