Contact the support team to merge duplicate agencies for you (1-888-764-0633) and then follow these steps in the future:
If Agency is not yet listed under the [Agencies] tab:
Go to [Admin] >> [Add New Agency +] button.
Enter the Agency's contact info here as well as the name/email address for the Agency Administrator (Primary Contact).
Then you can click the [Add Agent] button to add additional agents.
If Agency is listed already...
Go to [Agencies] tab and click on the name of the agency.
Next, click the [Add Agent] button to add additional agents.