I owned a Garmin smart watch (Vivoactive 3) for five years and it still works fine but the watch when fully charged barely lasts 8-9 hours... it needs a new battery.
I also checked a couple of my local watch dealers/repairers and they suggested I contact Garmin about a repair.
So I did, I phoned the Garmin Support Centre in Australia about getting the battery replaced, either by them or a recommended repairer. And their suggestion was to exchange it for a small fee... I didn't enquire whether this was a new or re-conditioned smart watch.
I declined their offer as I was hoping for a local solution. Maybe I was too hasty.