BiG BuG !!!

hello, sorry for my english but ... there are a big error when i send a mail from webmaster@alloocash.com to webmaster@alloocash.com the mail go in yepla@alloocash.com and when i send a mail from yepla@alloocash.com to webmaster@alloocash.com the mail go to yepla@alloocash.com ! :( i don't understand i have 2 home different yepla : /home/mail/yepla/ with Maildir webmaster : /home/mail/webmaster with Maildir i use postfix and courier-imap-ssl i have 4 users which use roundcubewebmail and the bug is only on this 2 adress plz help thx Yepla