@Mitra, Amit Kumar (Extranet)
Thank you for your post and I apologize for the delayed response!
When it comes to AzureAD group owners, when a group has no owner, group-managing administrators are still able to manage the group, but it's still recommended for every group to have at least one owner. In your specific scenario, once owners are assigned to a group, the last owner of the group cannot be removed. Therefore, you'll have make sure to select another owner before removing the last owner from the group.
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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