My name is***** am sorry to hear that you are having this issue.
I will be glad to assist you with this.
That is the two step verification process, try turning it off and then sign in again on the Apple TV.
To turn off two-factor authentication, sign in to your Apple ID account page and click Edit in the Security section. Then click Turn Off Two-Factor Authentication. After you create new security questions and verify your date of birth, two-factor authentication will be turned off.
Let me know if that works for you please.
Let me know if this does not work and we can try another solution.
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