It might be the watch faces hasn't actually been sent to the watch yet. I've seen that take a bit of time (30+ minutes)
Which watch faces are you trying? I can give one a try if you keep having problems.
I called Garmin Support about the issue and they could see there was a sync issue. They had me remove the device from my profile and then re-pair the watch with my Connect account. This seemed to fix everything. I called yesterday afternoon and haven't run into the problem again.