Right, I didn't think about that at first, because I just moved nano3 from one room to another, I mean what can get wrong in 2 minutes, something went wrong obviously, don't know how and why.
Plus, device was working but in lower watts, showing network connection problems, so my focus was on that.
Today I decided to test it with different adapters, some adapters are not supported (nano3 says so on the display), I was using stock adapter with stock cable btw, which came with the device, interestingly enough macbook pro adapter 140w doesn't even power the device on. Anyway I had one usb-c-usb-c cable which worked with that stock adapter.