You have the possibility to define an unsubscription list (or blacklist) specific to your campaign.
To do this, click on the button "Unsubscribe" present on the screen of management of list of recipients as well as during the edition of the header of your email.
If you have not yet created a blacklist, you will only be able to use the default unsubscribe list. If you have already created unsubscribe lists, you can select them here.
The addresses that will be present in the chosen list of unsubscriptions will be automatically removed from your list of recipients at the time of sending.
Similarly, when a contact clicks on your unsubscribe link, it will be added to the unsubscribe list you choose here. You can also click "Manage blacklists" to add addresses to an unsubscribe list or just create a new one.