Email accounts are using more than allocated Disk space for email account

After the recent update some email account users email usage is showing more than allocated space, It was an big BUG in CWP.
it was our experience and those customers are not able to attach file to their email because of this bug. Screen shot added below let me know if any one can help on this . Continuous Bug in CPW making us to move back to CPanel

After recent update on CWP the email account usage are showing out of allowed space for each account, there was issue in CWP and it is a BUG. how these email users can use more than allow space for their email usage ? IF CWP is working fine this will not happen so below person always say there was no issue in CWP from our expreience CWP always have BUGS and it was not resolved or sorted yet.

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