As the admin user of your account, you need to submit a ticket to Support in order to get new roles. Please submit this request with the e-mail address linked to your user role because our Support team will need to verify that you are indeed an Admin.
Note that for security reasons, such cannot be done over the phone. You will receive a confirmation that the roles have been added to your account.
Remember that you can only grant users roles that you possess yourself. You can find an overview of all roles here.