Unable to connect for playback
Can’t watch anything on Apple TV
3920X,
Another user (mygreensocks) suggested this procedure from Roku Support staff, which reportedly helped several users.
1. Remove the Apple TV app,
2. Shut off and unplug the TV (or streaming device),
3. Wait 30 seconds,
4. Plug the TV (or streaming device) back in,
5. Reload the Apple TV app.
Else try the Network Connection Reset, as mentioned by user Jarieta.