To resolve a blacklisted domain, you will need to switch out the default domain provided by SUPPRESS at the beginning of your service term. SUPPRESS provides a single default domain for collecting unsubscribes which, once blacklisted, can severely impede the deliverability of any email messages with that domain inside them. To resolve this issue, we recommend that you procure a few custom domains, and set them up accordingly in the system to mask over the blacklisted domain(s). This would ensure continuity of deliverability that would be otherwise negatively impacted by the compromised default domain.
Typically, domains can be blacklisted for a couple of reasons, such as a publisher hitting bad email addresses; commonly known as spam-traps, which are set up by a blacklisting site. Another reason could be the result of a publisher repeatedly mailing recipients who hit the spam button in their email client, and then report those emails to these BL sites. The only way around this is to change your domain. You can set up additional domains in your account any time by using the Custom Domain feature, located in the sub menu of the Settings tab on the navigation bar.
To learn more about adding Domains to your account, please review this article: What Is OPTIZMO's Managed Domain & IP Service?