Does tyntec offer an unsubscription API endpoint? Yes. To better manage unsubscriptions, there are two options provided. 1. Delete a contact via API call https://api.tyntec.com/reference/support_inbox/current.html#support-inbox-api-Delete%20a%20note 2. Block a phone number via API call https://api.tyntec.com/reference/support_inbox/current.html#support-inbox-api-Block%20a%20contact