So, did Garmin ever reply? They sure as heck don't reply to my queries :( (having same / simular problem here and now for 2 days (!))
If the symptoms are the same as in the OP, then it could be a problem of a full or dammaged storage on the device, or perhaps a problem of syncing.
As for the storage - connect to the watch with the USB cable, and check out the free space on it (on Windows in File Explorer, using the Properties of the drive). You can also test the storage - again with the built-in function in File Explorer, or with some dedicated USB storage repair tool.
As for the syncing, review the Sync Audits on the GC app (Menu » Settings » Device Sync Audit), and search for any errors or suspicious messages in them. Note that you can use the buttons at the bottom to navigate among the past audits.
I get everything except HR-data synced succesfully. When looking in the log it shows this line, indicating which data types are being synced:
#Types=[4, 32, 35, 38, 44, 41, 49, -11]
Any idea what these types represent? Are one them HR-data? The last one (-11) looks a bit strange, being a negative number...
Regards
Leif
I get everything except HR-data synced succesfully.
The most common reason for it is documented here: Data is Missing from My Garmin Account After Syncing
Another similar case was resolved with it just today: Resting/High heart rate not showing on app