@Ahmed Mahfuz , Thanks for posting in Q&A. Based as I know, when we add group under Remove (update). it will only remove the same group from the local administrators group. The user in the group will still be kept. Could you confirm if the group you added is under local administrators group on the affected device? And if our issue is the group still exist under local administrators group after we apply the policy.
If you want to remove the users in this group instead of the group from local administrators group, you can consider Add (Replace): action to only add the users you want. Here is a link with more details:
Hope the above information can help.
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