Thumbnails displayed only in debug mode

[twin-elements]

Hi.
When I turn off APP_DEBUG=0 debug mode, some (not all) of the thumbnails stop displaying on the page.

I am using symfony-config write target.

If I am logged into the admin panel, more thumbnails appear on the page, but not all of them.

When I run the pimcore:thumbnails:clear --type=image --name=my-thumbnail command, the thumbnails are deleted from the /public/var/tmp/thumbnails/ folder but are not re-created.

In the logs there is only:
[2024-06-27T08:54:42.987620+02:00] pimcore.ERROR: Unable to generate image thumbnail, see logs for details. [] []

Sometimes it is the case that just refresh the page with Ctr+F5 thumbnail, even though it is on the server does not display. What follows is a 302 redirect to /bundles/pimcoreadmin/img/filetype-not-supported.svg
if I go directly to the path /var/tmp/thumnails/.... then the thumbnail will work

Has anyone encountered this problem?
I can't leave the application in debug mode forever....
I am very much asking for help.