The first time I've installed GOGG2 went smoothly, not all the games across all my accounts were detected but that's not the issue. After restarting the PC the app just won't log in. It keeps trying to log in, fails and asks for password again, if I use a wrong password it alerts so immediately.

I have no idea why it's happening but I have a gut feeling that when I installed it I was connected with NordVPN (but assigned to my own country) and now I'm not using it which is strange since NordVPN more interrupts me from logging into stuff and now it is turned off.

I had the same problem with the old version, tried updating to ver 2.0 & stil happening. I have to restart the PC to be able to log in but it’s only a temporary fix as it can happen again on the next restart or several restarts later.
I receive an error message when this problem happens on restart saying that GOG has to close.
I thought it might be a network problem so have reset the settings under network & will see how that goes. If it doesn’t fix it then it’s either a GOG or a Microsoft problem.