Setting up bounce handling is not required if using the AWS SES integration plugin. The integration will automatically configure your bounce handling.
What you must do is set up a new email account called firstname.lastname@example.org where ‘mydomain.com’ is the domain of your site.
Then, go to MBRCRM > Settings > Email.
Scroll to the section titled Email Bounces.
Fill out all the fields with the IMAP information of your new email inbox so that it looks something like this.