AppleTV cant login in itunes store

If you have a legacy Apple TV (2nd or 3rd generation) and two-factor authentication for your Apple ID, then you may be asked to type your password followed by the six-digit verification code directly into the password field. Additionally, there is a time limit, after which the code becomes invalid.

Try this: First enter the characters of your password (do not submit yet), then manually request a new verification code, then append that code to the password (no spaces or other separating characters), and then submit. That should help you get passed the time limit.

Can you verify the credentials (account name+password) on other devices? Can you sign in to e.g. appleid.apple.com?

Did you perhaps receive a verification code, even if not mentioned on Apple TV? Do you have two-factor authentication for your Apple ID at all?

If the issue persists after a restart of all devices involved, including the network gear, then please ask the Apple Support staff for further assistance. Contact Apple for support and service (phone numbers) or start your support request online (chat/​email/​callback).

Verify that Apple TV (still) has its Settings configured for AirPlay receiving ‘On’.