I have been dealing with this too. Definitely due to moisture. In my case, brought it with me into the shower and it got a little wet. I thought it had better water resistance. (my bad) My belief is that the "button" part went bad. Samsung Gear S3 frontier (SM-R760) Volume flex cable GH59-14696A https://rounded.com/samsung-gear-s3-frontier-sm-r760-volume-flex-cable-gh59-14696a.html In the states you can get it through SamsungParts.com or call 800-627-4368. I just ordered the part for ~$17 total and am hoping it fixes the bootloop problem. Considering that the watch thinks both buttons are being pushed all the time which is why it goes into the loop, it should be the fix.