You can quickly unaffiliate any subgroup from a parent group from the parent group’s Manage Groups menu.
1. Click Manage Groups.
Administrators or moderators of groups can change affiliate subgroup status from the left-hand sidebar. Click Manage Groups in the parent group’s sidebar.
2. Remove Subgroup.
Find the subgroup you want to unaffiliate, expand the more options menu, and select Remove Subgroup.
The subgroup will become a regular group and will be unaffiliated with the parent group.