After you modify the approval, you chose whether to resubmit the approval process to approvers. When you modify a submitted approval, the Approvals window displays and prompts you to add comments to send to new and existing approvers. If you want an approver who already responded to view your changes, check the approver's
Request Reapproval check box. Whenever you want an approver to reapprove, the system increments the approval round number.