iTunes sign in on Apple TV

There is 2 work arounds, either sign-out/in by going to settings>iTunes store>Apple ID> sign-out, then add new Apple ID and sign-in or when being asked to sign in enter and submit Apple ID, then enter password but DON'T submit! At this point must go to trusted device (device u receive code on normally) and go to settings>iCloud>click on your name/Apple ID>password & security>get verification code. Then enter code on Apple TV right next to password, no spaces anywhere, and submit!!!!! Try one of these options

If you have Two factor authentication on Apple ID then it will not work, since old TVos has no dialog for verification code. If thats not the case try to contact iTunes

If these don't work, try unplugging Apple TV and rebooting network. Then trying to sign in one of the ways I suggested, if necessary