Apple Watch 5 not recognised by Apple TV 4k

Hello community,

for a months I am trying to solve issue with my Apple Watch 5 not recognized by Apple TV 4k. It used to work perfectly. I was able to ask Siri to pause Netflix movie while watching, or rewind. But since months ago, this is not working anymore.

I can not see my Apple Watch under Apple TV devices. Yet I can see my Apple TV in the remote app on Watch. But Siri commands, neither Now Playing feature not working.

Watch is on wifi, ATV connected to the same router by cable. I reset Watch, I connected ATV to the same wifi, unpaired and paired my iPhone, but nothing is working. Nothing.

Any advice please?

[Re-Titled by Moderator]