Everything connects fine, calibrated with Rouvy, because Zwift can’t, start a ride and about 1 minute in, get a notification that setting aren’t correct and no one can me anymore. The trainer works fine, changes resistance and records everything fine. This post is the M2s last chance before I send it back.
The only thing I can suggest (as a H2 not M2 owner) is to ensure you have no other device attempting to pair with the trainer and that you have device detection disabled in things like Zwift Companion on a phone. In my case it was common to have devices fighting for the H2’s connections until I disabled ZC’s detection.
How are you connecting to the trainer? I had a few weird things with my M2 when I first got it and was connecting via bluetooth, but once I switched to ANT+ FE-C connection, those largely went away.