Hi there,
I have got a recent run which seems to be perfectly fine on the device itself (can see map and overall stats), but which can't be synced somehow.
Initially, when syncing as usual for the first time, there was a message in Garmin Express stating that "some files couldn't be synced". All further retries eventually lead to a very quick syncing process (2-3 seconds) upon which Garmin Express states that syncing was successful (the actual run was 18km and took more than three hours, so should transfer much longer). I also removed and readded the device, without any success.
If I create a new run, it syncs absolutely fine, so I am assuming, the issue is caused by the serverside somehow thinking, the run has been synced already. That probably means getting my hands dirty inside the library and app settings (I am on Mac).
Any advice is appreciated.