Two weeks ago, I posted that exact same problem that many users encountered (see below).  Then it was solved by Spotify.  And today I have the same problem occuring again... Someone else experiencing that ?

My Chromecast does not appear in the list of devices to connect to on the Spotify Android app (Galaxy Samsung S7, Android 7.0).  Other devices are listed (such as my PC).  I can cast from all other apps (such as Netflix) from that same phone.  I restarted everything (cast, router, phone...) and reinstalled Spotify (including removing all cached data)...

All versions are up to date...

It was working this morning, it is broken now. Grrrrr