All advertisers, regardless of the selected payment plan, must add a billing contact to their buy-side account before launching ads with Mantis.
To add a billing contact to your account:
Log in to your Mantis buy-side account (or sign up for a new account)
Navigate to the Billing tab in the left navigation
Click on the Billing settings tab at the top of the screen
Fill out the required/empty input fields under the Billing contact section (as shown below)
