As described but also intermittent resistance from the turbo. Reset, restarted, reloaded in… no matter what I do the Companion app won’t connect to the workout and give me the relevant dashboard.
Make sure your ZC and Zwift apps can see each other on the network, e.g. not using mobile data. Sometimes a router reboot can fix it.
Steve is correct that the problem can be that ZC and Zwift don’t think that they are on the same network.
I solved this problem two weeks ago. My ZC (Android on home Google Mesh wifi) and Zwift on my desktop (Windows 10 hardwired to my network switch, which was plugged into the Google Mesh RJ-45 port) stopped seeing each other when I loaded Zwift on the Android (for running on a treadmill at the gym.) Solved by removing Zwift from the Android, unplugging my desktop from the switch and plugging desktop into the Google Wifi router. Turned off the other Google wifi hotspots at home so that ZC on the Android would have to connect through that main Google wifi router. ZC started seeing the game again when I was running Zwift on the desktop connected directly to the Wifi router. Then unplugged the PC from the Wifi router, plugged it into the switch and plugged the switch back into the router. Game now shows up on Android device again. YMMV. Good luck