Steps to edit an existing campaign:

1. Go to Line Items: Go to the Line Items tab in the left navigation menu.

2. Select Line Item: Select the Pencil/Edit icon for the line item that you want to edit.

3. Edit Line Item: You can edit the Line Item Name, Start Date, End Date, and Line Item Budget, Bidding, and other optimization options as per your requirements. You can not change the retailer once the line Item is created.

4. All set: Click Save and your line item edits will be applied.