Removing unused entities

I have some unused entities and don’t know how to get rid of them. The attached screenshot shows the same entity and I’d like to remove media_player.gallery_ok. This is added via configuration.yaml and media_player.gallery_ok is no longer in configuration.yaml. I can’t remove it via the UI. How to remove unused entities?

Were they added by the mqtt integration?

No, manually by me in configuration.yaml. I’m setting up my Control4 amp (Home Assistant direct control of Control4 AMP and Tuner (no plugin needed) - #75 by OtisPresley).

The entity media_player.gallery_ok no longer exists in configuration.yaml but still shows in entities