The issue occurs under the following circumstances:
The Usergroup needs to be populated with existing Users.
With Automation Engine only environments, the issue does not occur.
When adding newly created Users to Usergroup with existing Users, the "old" Users were decoupled from the Usergroup and set to inactive in ARA environment.
Investigation
Please see screenshots for better understanding:
Adding new Users to the Usergroup using LDAPSync....
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