I have been running Zwift for many months on my PC, and only this week started accompanying those rides using the companion app. However, I immediately noticed that when I exited the ride on my PC, I no longer was shown the Save-And-Exit (and upload to Strava) menu - it just exited and closed the game immediately. My rides were not being automatically uploaded to Strava (and I had to download the FIT file from my.zwift.com and manually upload to get the ride on Strava).
So, I make sure now that I first exit the companion app on my phone, THEN I exit the ride on the game program on the PC, and all is correct and normal - I get the save/andSaveStrava menu, and it works.
Somehow the companion app is interfering with my Strava connection. I’ve heard from other riders that this may be true for the Garmin connection.
Windows10 PC - Zwift game
Google Pixel 3 (Android) - Zwift companion app.