This is the mail system at host mail.postmail.com.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to <postmaster>

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                   The mail system

<prosupport@problemdomain.com.org>: mail for problemdomain.com.org loops back
    to myself
 

----------------------
This issue was caused because postfix's list of destination domains was not updated with the domain in question.  All you have to do is update it so it knows to accept mail to that domain.

Solution:

vi /etc/postfix/main.cf

Edit the "mydestination" and add your domain to this list:

mydestination = domainbla.com,
                brokendomain.com

Edit the appropriate MySQL table if you're using MySQL as the backend for Postfix

service postfix reload