Approver edits requisition

Morning,

I wonder if anyone can help.

We have a process where a user raises a requisition and submits it for approval.

The approver clicks edit requisition and increases the qty on the req.

The approver can then save this change and if it is still within their sign off limit they can approve the req.

Is there a way to force the requisition to go to the next approver in the chain? Because the approver has amended the req, they are technically approving their own requisition.

Thanks

DD