Reassignment of user input task - Manager to restrict only within the group

Certified Associate Developer

Hi,

I have a user input task assigned to  Approvers group (which has Manager access). The process model security also has Approvers(group) - Manager access.

I want to control the reassignment by users of this group to do within the group of Approvers but not from all users and groups.

I tried the below setting, but still I see "All users and groups" option shown. 

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