Thanks for reaching out. Just to confirm with you, have you tried the troubleshooting here? https://www.samsung.com/us/support/troubleshooting/TSG01003250/ If this is not helpful, please send a private message with the serial number or IMEI number of the watch. http://bit.ly/2XERsky
I've had my Galaxy Watch for about a year and a half now and the Back button has now stopped function entirely. I was wondering if this is a common problem that can be fixed by a reset or firmware update or if there's a repair option I could use to send the watch in to be fixed. Thanks!