Create Person Security Profile with AoR and Position Tree

Summary:

Cannot select position hierachy as scope of responsibility in creation of person security profile. Thus, position tree cannot be referenced rendering our plan to secure person access via AoR and position tree useless. However, the value is in the system lookup controlling the LOV that appears when creating a person security profile -- its just disabled. Why is that? Is there a way to acriv

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We are currently trying to create a role that is only able to view HR people. Thus, we created a position tree, referencing only HR positions. we then went ahead and assigned the appropiate AoR on the person: