The "Contact DND" workflow triggers when there is a change in a contact's Do Not Disturb (DND) status. DND is a feature that customers can enable to opt out of communications when they are no longer interested in a service.
By using the "DND flag is" option, you can toggle a contact’s Do Not Disturb (DND) status on or off. Activating DND restricts all outgoing communications to the customer, while deactivating it restores open communication with the customer.