@Пономаренко Руслан
Do you have any operations when you installing?
Based on my knowledge, When you install Skype for Business Server, one of the tasks that was performed by the Setup program gives the RTCUniversalUserAdmins group the Active Directory permissions that are needed to manage users, computers, contacts, application contacts, and InetOrg persons. If you have disabled permission inheritance in Active Directory, setup won't be able to assign those permissions. As a result, members of the RTCUniversalUserAdmins group won't be able to manage Skype for Business Server entities.
To verify that management permissions are set on a container, run the Test-CsOUPermission cmdlet followed by the distinguished name of the container and by the type of permissions that you are verifying. For more details about its steps, you could refer to: https://learn.microsoft.com/en-us/skypeforbusiness/manage/test-admin-permissions#running-the-test
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