My Apple TV 4K or Apple TV HD control tv and receiver option will not turn on. What should I do?

Unless someone else chimes in with a good idea, I would suggest to contact an expert from the Apple Support staff for further assistance. Contact Apple for support and service (phone numbers) or start your support request online (chat/​email/​callback).

Do you have a TV and/or receiver connected that all have HDMI-CEC activated?

Try resetting the HDMI connection by unplugging the HDMI cable on both ends, and then reconnect.

Else try restarting both the Apple TV box and the TV (real restart, not sleep-wake).