Chosen Solution
It seems to work when on the charger but when I take it off, it won’t come on.
Hi, It seems as though the battery has failed. Here is the Ifixit guide on how to teardown the G watch. This shows the removal of the battery. Unfortunately, I cannot find a battery online but once you have opened the watch, by using the details printed on the battery you may be able to find one. LG G Watch Teardown Hopefully this is of some help.
