Delivery Buttons enable delivery people to easily deliver packages to your office. There are two ways to set up delivery notifications. You can either blanket notify one or more people of all deliveries or ask delivery personnel to select their recipient, just like visitors select contacts. 

To notify one or more contacts for all deliveries, start on the Button editing page. From that page, select "Existing Buttons" and then "edit." Then, scroll down to the "Select Delivery Contacts" section. Ensuring that "Contact Required is toggled off, select all contacts you want to be notified. Don't forget to save!

To require that delivery personnel select who the delivery is for, you'll instead toggle the Contact Required button on. Then, select all Contacts you want delivery people to be able to select. As ever, save before editing the page.