Postfix Maildir does not return over quota mailer-daemon

[Kniar]

Hello,

I have postfix with Maildir (/home/USER) on CentOS. All works fine except when a user is over quota. The message is kept on another part (/var/spool/mail/USER) and no mailer-daemon is sent.

I think it's a normal way that the message is first written in /var/spool/mail/USER. The message is then moved to /home/USER/Maildir/new when quota on this part allows it. If over-quota, the message can't be moved and stay in /var/spool/mail/USER

I don't want over-quota messages be stocked in /var/spool/mail/ and I want mailer-daemon be sent to sender.

Any idea to fix it ?