I’ve merged your support topics to keep the conversation in a single place. Are you encountering an error with your credentials, or does the browser redirect not open Roon again after signing in? Please share a screenshot if applicable.
I’d first disable any adblockers or content blockers in your browser and clear your cookies. Test logging in again.
If that doesn’t work, then please attempt to sign into the Roon accounts page in a browser directly outside of Roon. See if the session carries over to Roon on the same device.