First, navigate to the directory:
Next, click the company you want to edit:
If there are no users, click Add User:
Once the user is created, enter their contact info, and select the Primary Contact checkbox:
Click Create and this user will be added as the primary contact.
If the user that you wish to designate as the primary contact already exists, click Edit next to their name.
Then select the Primary Contact checkbox and enter their contact information.