We’ll need some additional information to take action on this report. Do you use streaming services with Roon, your own digital library, or both?
Try signing out of any streaming services in Roon Settings → Services and then signing back in.
Please also try disabling and re-adding any Watched Folders pointing to your local library folders in Roon Settings → Storage.
Can you provide a screenshot illustrating the error?
Keep in mind some streaming services will rotate their catalogue as backend distribution agreements change. You might see albums become unavailable over time - in this case, they’ll be labelled “unavailable” at the track level in the Album details page.