Delete Users -> Delete Data

Hello Community!

The storage of my Cloud is full, but I do not have that many data saved there.
If I do a Backup, or look just at the folders there is always only 120GB space used.
But ive got a storage of 250GB. But still... its Full... and with a full server, you cant connect via browser.

A friend told me, that there might be some user in my Cloud, who had saved Data on his Account. As an admin I cant see, which User has what Data.

Is there a possibility to see it?
If I delete a User, will his saved Data also be deleted?

What could also be the source of my probleme of storage? I did not intend to pay for 250GB and only use 120GB

please show us of the result from the command

df -h

Disk space is used when it is in user accounts that are not deleted, and when there is still space available on the disk and space is used by deleted files that have not been removed from the users' deleted files folder.

Try emptying the users' trash bin:

Or deleting the users: