Same here, using Xiaomi Mi 9T with Garmin VivoActive 3. It does seem to sync when i have the app connected, but i dont receive any smartphone notifications on my watch.
I get this too - followed by the text "Android notifications have stopped unexpectedly. In order to restore notifications for your Garmin device, you will need to reboot your phone." I do nothing and things…
SOLVED the issue on my phone (mi 9t).
It was under battery saver options. I had to turn of "use adaptive battery"
Maybe your phone has a similar option, it's worth to check it out.
I get this too - followed by the text "Android notifications have stopped unexpectedly. In order to restore notifications for your Garmin device, you will need to reboot your phone." I do nothing and things seem to work (texts, etc still come through) but is this a bug?
Ditto with a Garmin Edge on a Honor 7s.
Means i've got to physically load the app after a reboot to try and get it to sync to the phone, and if it drops out, it doesn't appear to reconnect - great for setting up an emergency /incident reporting or using the live track service.
I have the same issue with edge 520 and oneplus 5t phone. It does not automatically upload activity when this notification is on. What I found is that if I save the ride on the garmin device and restart it, then it automatically uploads the activity.
Same here, Huawei P10 Lite. This is really disturbing...