Notification gets sent AGAIN when I make additional changes to a row

edited 12/09/19 in Smartsheet Basics

My Smartsheet tracks employee travel. They complete a form to request approval for travel, and then I go into the Smartsheet to approve it. I have a notification set up when I approve based on adding the "date approved," and an approval is sent to the user. However, when I go back later to add the final travel amount spent, the notification is sent AGAIN to the user. I want the approval notification to go to the user only once, upon initial approval.