I use my Sonos One speakers to listen to radio on TuneIn quite a bit. Around the beginning of this year (2021), a bunch of stations disappeared -- if I ask the Google Assistant to play them it says, sure, then says it can’t find what it’s looking for. The same stations still come up if I ask for them on other Google devices or my Cortana speaker, and certain stations still come up on the Sonos speakers.
Is there some reason certain TuneIn stations disappeared from the Sonos -- and only the Sonos -- system?