I have tried to set up a default courier email and phone number as a rule, however, I found that for some courier integrations like Amazon and Evri, the field must be with the correct phone number and email, as the couriers usually contact the clients in order to get delivery instructions if it needs it during the delivery.
However address details in general should be mandatory for any integration in general, this will avoid extra steps and errors to pop out constantly on the screen.
