Desktop - repeatedly I can't connect to the server

Hi, I use Mattermost on desktop (Win 11) longer than a year and in the last month repeatedly I can’t connect to the same server via external authentication (option at the bottom below the login fields). My tries often end by a message:

Redirecting to browser…

Authenticating in the browser, awaiting valid token.

… and nothing.
I tried to reinstall newest version of the app and first it worked. Bud after couple weeks I’ve got the same problems.
The server works as usual I guess, my teammates have no problems with connection.
Does anybody know, what’s the problem?