Thank you for following up on this with your screenshot!
I understand that you're trying to install the Apple Business Manager app but are having issues since it's showing in a provisioning state, and when running the Get-AzureADServicePrincipal command, the app doesn't show up in the list.
Based off the screenshot that you shared, I'm able to see the same thing within my Azure AD tenant and it looks like you'll need to Sign up for Apple Business Manager
and follow the Apple Business Manager User Guide prior to using federated authentication with MS Azure AD in Apple Business Manager. For more info - Configure Apple Business Manager for automatic user provisioning.
Add Apple Business Manager from the Azure AD application gallery:
To add the Apple Business Manager Azure AD app with Microsoft tenants, the administrator of the tenants must go through the federated authentication setup process, including testing authentication. When authentication has succeeded, the Apple Business Manager Azure AD app is populated in the tenant and the administrator can federate domains and configure Apple Business Manager to use SCIM (System for Cross-domain Identity Management) for directory sync. Use federated authentication with MS Azure AD in Apple Business Manager.
I hope this helps!
If you have any other questions, please let me know. Thank you for your time and patience throughout this issue.
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