Auto Approval for Buyer Returned lines

Hello Everyone,

Our requirement is mentioned below

Create requisition -> Submit for Approval -> Approved -> Requisition will go to buyer pool -> If buyer needs more information he will return the requisition to the requester. -> Requester provides the justification without changing quantity or amount-> Submit the requisition ->Since the requisition is already approved we don't need the approval again.

How to achieve this functionality?

Thanks in advance,

Yogesh