Quota Display Problem

In the virtualmin , edit virtual server page .

i find that the quota information is not correct .

Show as

Home disk space used (including sub-servers) 4.97 GB (3.42 GB by server administrator, 6.14 GB by mail / FTP users)

But the correct space used is , 3.42 + 6.14G = 9.X G

Incorrect at 4.97GB.

size is correct when i add the two information as the message.

where the system infomation to create the 4.97GB size ???