Can't upload featured image & Media Library images are gone

Hello!

I would like your help with the following issue, please!

When I try to add a featured image to a post, I get this error message: “An error occurred in the upload. Please try again later.” I had this problem for a long time now.

Also, I can’t find any previously uploaded images in the Media Library, although there should be hundreds of them.

The website is updated to WordPress 5.9 & Newspaper Version: 11.4, and my web hosting provider can’t find any issues (the server is running PHP 7.4).

I tried deactivating all plugins except the ones required for the theme to work but it didn’t make a difference.

Any advice would be highly appreciated!

Thank you!

Yes, thank you, problem solved!