To assign a new team member a Main Admin role for the primary Funding Account, you must first be a Main Admin yourself. The team member must also be invited to join your Business Account and added to the Funding Account user list.
Navigate to the sidebar menu > My Account > Admin Operations.
Under the Admins Management section, select Add admin under Admin Operations.
Select the team member from the list to add as an Admin.
You can view the list of Funding Account Admins under the Admins Management section.