This article explains how to manage bounced emails
If an email address is listed on this list, the email address has already been deactivated. Reviewing emails on this list is your opportunity to retrieve emails bounced in error, because of typos, or for other correctable reasons. You can either edit an email (reactivating the source's email) or confirm that an email is bad (it will stay deactivated and disappear from this list).
Go to the bounced email page.
You can use the filter to limit based on an organization or find a source by name or email address.
Hover over a line to see the Edit and Confirmed Bad (red X) buttons.
Clicking the Confirmed Bad (red X) button will immediately set the email address to a status of "Confirmed Bad". If the source has no other good email address, the source will be confirmed as unavailable in AIR. If the source has another email address that IS good, the bad email will be marked as bad, the good email will be moved into the primary email position, and the source will be available in AIR.
Clicking the Edit button will allow you to modify the email address.
When you edit the source's email address and click the SAVE (purple diskette) button, the source will be retrieved as an available source.
If you update the email address to one that exists for another source, you will see a Merge option (blue arrow).
Clicking the merge arrow will take you to the merge screen.
Merging an edited email address from this list with another source record, and committing the changes, will confirm the source as an available source in AIR.