Resubscribing an email address allows one of your contacts to continue receiving your email messages in the event that they may have accidentally unsubscribed from one of your campaigns.
What can contacts unsubscribe from?
Contacts can unsubscribe from:
How to Resubscribe an Email Address
If a contact has provided permission to resubscribe their email address, simply email support@followupboss.com with the contact's email address.