Image not showing in posts written by author

I’ve Solostreams WP-Radiance theme on my site that is under construction. The page is supposed to handle a number of users who will have the role of writers. Sometimes they shall also be able to manage pages on the site, for this I installed Co-Author Plus. Unfortunately, this resulted in that these users could no longer put images that they have uploaded to the media library in their posts. When they decide to add an image they can’t see the images that are already in the media library.
I have tried to uninstall the plug but the problem persists.

https://www.ads-software.com/plugins/co-authors-plus/