Plugins not appearing in admin panel, but they are in the plugins folder

Hi!

At first, I did nothing, my site was up and running, I was in a vacation. Then came an email from Jetpack that my site is not runing.
My site had only a white screen without admin panel or anything.

So i traced down the problem and found out that if I disable a plugin called Quick Cache, it would work, but now none of the plugins is listed in the admin panel. I don’t want to lose my plugin settings.

My plugins are still there in it’s folders but WP-Admin panel can’t see them.

Could someone please help me? My site is https://www.keto.hu