The Disable button turns off the Qobuz feed but does not log you out of Qobuz. Logout actually logs your account out of Roon so that you have to log back in.
And you are sure you are using the correct account credentials, etc etc.
You might try the next step and clear the cache. 1. Log out of Qobuz in Roon. 2. Shutdown RoonServer on the Nucleus+ Web UI. 3. Follow the steps in this post Qobuz login failing [Resolved - Cleared Cache] - #2 by ged_hickman1 4. After restarting the RoonServer, log into Qobuz.