[A] Go to the “Network” module. In the search bar on the right side, search the name of the party for which the email id is to be added. Then under “Actions”, click on the blue button that allows you to edit details about that party(1).
[B] In the new screen titled “Manage Network connection”, scroll down. On the right, click the “+” button next to “Billing Addresses”(2).
[C] Enter the details of the new billing address and then click the “Save” button(3)..