I am using a gear for more than an year, however my gear was not active for more than a month and when I decided to use it again, I have experienced the same issue, the gear was not charging at all. I started googling and found this is an issue with gear if you are not using it for long.
I found multiple solutions like opening a watch and disconnect the motherboard/battery and reconnect or hard reboot while connected to dock, however the solution looks scary as we are actually opening the watch, I was not sure with warranty after opening the watch as well.
I found one more solution, which was pretty easy and handy. The solution was “Charge using your computer/laptop”. First I tried with a computer, however it did not work then I tried with Laptop and IT WORKED. The only difference between Computer/desktop and laptop was the admin rights. I have admins rights on Laptop.
I am looking for technical justification for not working from AC charger and working from Laptop USB, but my issue has been resolved. Thank you my laptop