A while back my sensors stopped working. I quit using the watch for a while, hoping for another update to fix it. Reading these boards, it appears to be a common issue after a particular update delivered by Samsung.
How do I get this working again?
It also happened to my gear s3 frontier and i have reset more than 3 times to no effect. i almost lost hope in this watch. i already reset to factory settings and even deleted all the saved data ( 3 years of data lost).
however doing some silly things seem to solve the issue. this problem happened after the latest firmware update somewhere in month of July 2021 when i updated manually.
This is what i did and i dunno if it will work with yours.
By luck i just tried pressing the 2 buttons on the right together for some 10 seconds and it rebooted. again i tried pressing it together for another 10 seconds.
After that all the sensors worked and i am glad to know i didnt fry the sensors during the update since that is what happened to my Gear Fit 2 Pro ( also the chip died after firmware update and samsung replaced it)