Workgroup admins can also add API users to their workgroups from the Secure App Service portal.
Alternatively, your service manager can contact DigiCert support to get them to perform the following tasks:
Secure App Service requires two factor authentication for all API users. You must have an active API user with valid credentials and a client certificate to use the SAS API.
After you have the API role and have received your invitation email, you're ready to pick up your certificate.See Picking up and installing your client certificate for two factor authentication.