Same problem here.
In Gear Manager, I go to Fitness>Menu>Sync Now and it says "Sync Complete"
Then, I go into S Health > Settings > My accessories
It says my Gear is connected
I tap on the sync icon
It says "Syncing" for about 10 seconds, then says "Failed to sync. Try again."
Kind of makes the fitness apps on the Gear useless if the data can't be imported into S Health.