The error message "License has been reached" typically indicates that there aren't enough available licenses for the product specified in the group. Even though you mentioned having four available Microsoft 365 Enterprise E5 licenses, it's possible that those licenses are already assigned to other users or groups, or there may be other licensing issues at play.
To resolve this issue, you can check the following:
- Available Licenses: Go to the Microsoft 365 Admin Center and navigate to Identity > Billing > Licenses > All products to see how many licenses are available and which users or groups are consuming them.
- Reassign Licenses: If you find that there are users or groups with licenses that are no longer needed, you can unassign those licenses to free them up for new users.
- Check for Conflicts: Ensure that there are no conflicting service plans that might be preventing the assignment of licenses.
If the problem persists after checking these points, you may need to purchase additional licenses or investigate further into the specific configurations of your subscription.
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