Each email address that triggers a hard bounce response is automatically excluded from any email traffic for a defined period of time and added under BOUNCED EMAIL ADDRESS. You can view a list of bounced email addresses at Lists > Relationships > Bounced Email Addresses.
Message will not be sent to any Email addresses in this list until they are removed from here.On this page, you can also remove email addresses from the list to include them in email campaigns.
To remove an email address from the Bounced Email Addresses list:
Go to Lists > Relationships > Bounced Email Addresses.
Check the box in the Delete column for each email address you want to clear the bounce history for, or you can click Mark All to select all email addresses in the list.
When you have cleared the bounce history for an email address, you can send messages to that address.