I and apparently this other user are also experiencing this issue, started within the last half hour or so. After logging out/removing the account and attempting to log back in, during the login flow it pretty much immediately says “Failed to reconnect. Please retry later. There was an error authorizing with TIDAL: Unauthorized. Please try again.” (this is before the login via browser completes). After successfully logging in and clicking “Open Roon” from the browser prompt to complete the authorization, nothing happens.
EDIT: Appears to be resolved now with Roon services being restored per the banner