Shared content disappearing

Hallo Guys,

since I am new to this forum let me say hello, nice to meet you.

Currently we are running into the issue that shares generated by users are beeing lost.
I am mounting several smb shares via my fstab and point external storage of the type “local” to the mountpoints.

This is working fine for several nextclouds for month now.
I recently had the first issues with sharing that resulted in a wierd bug of the users not beeing able to access the shared folders but downloading empty files with the folder names instead.

Reorted here with logs:

The fix was to disable and reenabeling sharing for the broken shares.
This deleted all the shares and links but the users were able to work again after that.

Now the shares are lost without touching this “enable sharing” checkbox.

This is leading to several clients trying to upload to non existing shares, shoving lots of data into thier local profile and exceeding thier quota. Also generated links are embedded into documents and websites that now are broken and have to be remade and fixed by hand.

I do have backups but i would really want to understand what could be causing this.

Any ideas where to start digging?

Kind regards,