Wrong used disk space in VirtualMin

I have a a virtualserver with a (IMHO) wrongly used disk space count (it’s a Magento installation).
Home disk space used (including sub-servers) 686.05 MB (686.05 MB by server administrator, 0 bytes by mail / FTP users)
Space used by databases 182.02 MB (182.02 MB in this server, 0 bytes in sub-servers)
Total disk space used 868.07 MB


But the /home/domain folder is only 480MB and not 686MB

The space disk count of other virtualservers I checked is ok.
What can be the problem? It sums something outside the home? Logs?

p.s. nginx logs are outside the home dir

does anyone have some ideas about this issue? :frowning: