My phone can operate the TV and sign it in. In the Home app, the TV is "not responding". On a screen of the TV I saw a message iOS 16 is required.. so would this be my problem?
What phone do you have? What iOS is it running? Have you tried updating to 16? What TV do you have? Does it always show not responding or only when the TV is turned off?
You really do need to give us more information in order for us to help you out