Hoping someone can help.
I have been using Tidal with Roon for a while now and its always behaved itself, but earlier this week it wouldn’t log on. I use the very same Tidal user ID and password in Roon as if I was accessing Tidal directly. On Roon it says ‘bad name or password’, they are both correct if I access via the browser directly.
I would try logging in via the TIDAL web player to see if it works (listen.tidal.com) with the same account, and afterwards try rebooting your Core or possibly refreshing the Cache folder. If these steps do not resolve the issue can you provide some more information regarding your setup?