Albums deleted from server still show in app

[reonb]

I am running Mimimserver on a synology NAS. I have several hundred albums. I have deleted some albums from the server, but they keep on showing in my App (Marantz). I rebooted everything, but the problem remains. Now (after one day) albums still show as folders, but without thumbnails. When I open them in the app, it says it has been deleted.

How do I get rid of deleted albums showing in my app.

Can I manually delete the Mimimserver cache files on the server, or will it cause a problem?

Hope someone can help

Reon Brand