Not deleting old thumbnails from database

Hi there,
I have been using the plugin to clear our old thumbnails created by my old theme (about 20 per image…) all good and I managed go reduce the size of the site quite a lot. I’m also using the Shortpixel plugin to compress images and everything was working fine untill the Shortpixel started picking the old sizes as “non existing files”. Then I realized If I go back to old images (all the old sizes still appear even tho this was cleaned up on a raw clean up. I have tried several things but this sizes still apear like missing images and with this the shortpixel fails to compress as there are to many unreached images.

Any advice on how to clean up the sizes for good?