Hi Fred,
I’ve shifted your post into Support as you should not have to login to Tidal all the time. Something is wrong and needs to be fixed.
In order for Roon’s @support team to better assist you, please provide a brief description of your current setup using this link as a guide.
Make sure to describe your network configuration/topology, including any networking hardware currently in use, so they can have a clear understanding of how your devices are communicating.
What happened here is that Tidal changed their login format to a browser based system and Roon has had to adapt. It might also help if you could tell Support which OS your Core is running under and what browser is asking for the login details.