Apple TV still won’t turn my tv off

Please use both Apple TV remote isn’t working and then Control your TV or receiver with your Siri Remote or Apple TV Remote

• TV manufacturers can choose to support any subset of CEC that they want. Not all TVs with CEC support will support power control (both ‘On’ and ‘Standby’). See your TV manual for details, or ask your TV manufacturer.
• TVs will have their own activation setting for CEC if they support any CEC commands. The setting on the Apple TV box alone is not enough.

Sorry if I wasn’t clear. Your Apple TV’s settings have nothing to do with your TV’s settings. The TV itself has to support HDMI-CEC also. Some TVs support the full set of commands, others only support certain subsets of commands. As has been suggested, consult your TV’s user manual to find out.

The problem is with your TV, not the Apple TV box. Check the manual for your TV to make sure it supports HDMI-CEC and that it is enabled.