Is it a Sony TV by any chance? Only there are some recent reports here in the community that some Sony products (mostly Turntables) have not been working with some Sonos products.
However, either way it may be a Bluetooth profile compatibility issue and the best way to deal with this is to reproduce the BT pairing/playback issue and then submit a Sonos system diagnostic report from within the Sonos App, note it’s reference and then contact/chat with Sonos Support Staff via this LINK and see what the Staff can perhaps suggest to resolve the matter.
It’s also somewhat common to not realize the Sonos device is currently paired with another Bluetooth device, like a phone, and not realize that you probably need to turn off Bluetooth on that device before the Sonos can ‘connect’ to the TV’s signal.