[Dovecot] dovecot:mail storage creation failed with mail location:mbox:/HOME_DIRECTORY_USED_BUT_NOT_GIVEN_USERDB/mail:INBOX=/var/spool/mail/test1@poste.tn

Hello I am working in a project and during my work an error has appeared in the use of the dovecot e mail server Squirrelmail an error occured:ERROR:Connection dropped by IMAP server and in the log mail we find: mail storage creation failed with mail location:mbox:/HOME_DIRECTORY_USED_BUT_NOT_GIVEN_USERDB/mail:INBOX=/var/spool/mail/test1@poste.tn child 5757(imap) returned error 89 can you give me a help i am waiting your response impatiently thanks