A cloud-based identity and access management service for securing user authentication and resource access
The error message you are encountering indicates that group-based assignment is not available due to your Active Directory plan level. Even though you have an E5 license, group-based assignment requires Microsoft Entra ID P1 or P2 edition specifically for that feature. Since you are unable to assign groups, you will need to assign users individually to the application instead.
If you believe you should have access to group assignments based on your licensing, ensure that your organization is properly set up with the necessary features enabled. You may also want to check with your administrator to confirm the specifics of your Active Directory plan and its capabilities.
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