Apple TV doesn't connect to iCloud

Hi all, I bought a pre-owned Apple TV for our secondary TV station at home.

When starting the Apple TV and resetting it, the Apple TV just asked me to connect to our Wifi.

It didn't provided me to opportunity to connect to my iCloud account (not sure if our previous Apple TV when setting it up).

Thus, I went to settings and tried to connect to iCloud using the correct account credentials (confirmed by the fact the system processed the two factor authentication). When completing the logon process, the Apple TV threw an error saying "logon not possible - iCloud currently not available". I tried to reset the Apple TV again and also made a software update. Both remained unsuccessful. I also checked the Systemstatus from apple, all services seem to run properly.

Do you have any other idea on what I can do to solve the problem?

Pre-Owner confirmed that the Apple TV was removed from his account.

Model A1469

TV OS: 7.6.2 (8144)

Many Thanks and best Regards,

Christian