Approve created element based on config list

So the point that I need to create an approval workflow for the "Orders" list that has columns Amount(num), Brand(Choice), Is Approved(bool) and make that workflow compare it to the "Orders approval config" list that has Brand(Choice), Min amount(num), Approver(text), the approver needs to be connected with the brand and the workflow must automatically approve new element in the Amount > Min amount, but while trying to add an Approver in "Assigned to" part of the "Start an approval", in Dynamic Contents I can't assign it to the "Approver" how do I do that?