By this method you will be able to put your watch into download mode and install firmwares by wires that you will need to solder inside your watch.
In case your watch keeps rebooting over and over and then dies, or you can't connect over wifi/bluetooth connection or you had an update and crashed your watch, so here is the method used to fix that problem.
Finally Samsung Gear S3 reactivation lock got unlocked. And there is way to reset reactivation of Samsung Gear Watches. Below is the method used for this purpose. This solution will help to reactivate a locked google account of watch. You need to download a Combination , and Firmware files and some other files used for this method.