That means it is a premium library.
If you go to the ‘Add Folders’ tab, are there several locations listed or only the root of your music collection?
Please do this: https://support.plex.tv/articles/202967376-clearing-plugin-channel-agent-http-caches/
Then stop your Plex server and restart it. After ~ 2 minutes perform the Plex Dance with all albums by that artist.
Let’s see if that changes anything.
