All agencies are required to have an advertiser account nested in their agency account before they can run creative with Mantis on a brand's behalf.
To add an advertiser account to your agency account:
Log in to your Mantis agency account (or create an account if you haven't already)
Navigate to the Advertisers tab in the left navigation
Click the Add Advertiser+ button
Fill out the required info to add a new advertiser and click save (as shown below):
