How do I set up a Resignation Approval Rule to go to Line Manager and then Approval Group?

We need to set up 2 approval rules for when an employee submits a resignation through ESS. We are on 23D.

1. Employee submits resignation and is NOT on LOA, route to Line Manager (we have this rule working fine)
2. Employee submits resignation and IS on LOA, route to Line Manager for approval and then to an Approval Group for final approval.

For rule 2, we can get it to route to the Line Manager, but when it routes to the Approval Group, it routes/assigns to the first person in the group for approval, once they have approved it assigns to the next person and so on. This is NOT what we want or need. We need it to go to the group and one of the members of the group claims it. I am newer to creating approval rules and am not sure what I am doing wrong or if what we need just isn't available for the resignation action.