I have this same issue, charger led blinks red and watch will not charge. I'm using all of the original gear, including the USB cable, that came with the watch. Model SM-R760NDAAXAR. 17 pages of users with this same issue @samsung please provide a fix for your customers.
My Gear S3 classic watch stopped charging to 100%. Every time it finishes at different level - it can be anything between 10% to 80%.
The charger is original. The battery is original. I can't see any solution here. @samsung please help
i had this issue after not wearing mine for a week and leaving it off the charger. The battery had run down to zero and it wouldnt connect to the charger. After getting nowhere with customer service i spent some time researching options and i found out that my galaxy s10 has a reverse charge option (remove phone cover to use) i turned it on and sure enough my watch connected, turned on and started charging. Once i hit 5% i put it back on its charger and its been working like it should ever since