How to change a Blacklist to Acceptable?

I recently received a scam e-mail “apparently” from our family e-mail address, that was sent to my Junk folder and the domain was accidentally blacklisted, so any e-mails from my wife are no longer sent to my Inbox, tho’ of course they are available in the Junk folder.

How can I remove the Blacklist filter from my own e-mail address ?