Not every day you see a Gear S3 Frontier in the wild. I repaired mine! They had faulty charging issues and they would overheat the batteries. : r/GalaxyWatch
Gear S3 battery drain after last update, resetting doesn't help - Samsung Community
How to Fix a Gear S3 Battery Drain
Gear S3, ancora problemi di battery draining | Soluzione temporanea - HDblog.it