Hello @FredS60 ,
Due to the legal and Compliance aspects of unsubscribing, we do have to ensure that a process is followed. If the contact is unable to find the automatic confirmation email we send out upon re-subscription, there is an alternative method. Collect an email from the contact's address explicitly stating they wish to be subscribed. Then call our review team, and they'll assist you from there to get the unsubscription overwritten.