Somehow Roon got disconnected from my Tidal account and now I cannot reconnect. I get a “bad user name or password” message, although I am positive I am using the right login info. I can login to my Tidal account without problem, with the same password and login on the Web or on my iPad app.
We often find that a reboot of the Core machine resolves this type of issue. Can you try giving the Core a reboot and let us know if there is any change?