Remove-unknown command deletes all backups with ZFS filesystem?

Hello,
Server version: 2.5.25
Server OS: Linux Debian
Filesystem: ZFS

When I try to run remove_unknown command from my server, it deletes all backups of all computers from Urbackup DB but not from disk.
At the end of output of the command it says that has no permissions to enter in the computer folder:

2022-09-07 18:12:36: ERROR: Cannot open “/RAID1/backups/RLOPEZ”: Permission denied (13)
2022-09-07 18:12:36: Removing dangling file entries…

After that, all the backups are deleted from Urbackup DB, I can´t see any of them from the web UI. But if I go to the filesystem, the backups are there.

I do not understand why, because I checked that there are full permissions in that folder (777).

This starts to happen with ZFS filesystem, before that I have been using BTRFS and this commands always works fine.

My ZFS config is:

ZFS Pool created,
“files” dataset created to store file backups
“images” dataset created to store image backups
“backups” dataset created to set as default folder for backups in urbackup config

I see that inside “backups” it creates subfolders for each computer, and inside it creates links to real backup folders inside the “files” and “images” datasets.

Any help would be appreciated about the correct ZFS config if it is wrong.

Thank you