Follow the below steps to edit the existing campaign:
1. Add Campaign: Go to the Campaigns tab in the left navigation menu.
2. Select Campaign: Select the Pencil/Edit icon for the campaign that you want to edit.
3. Edit Campaign: Customize your Attribution settings to fit your campaign's goal by selecting which Lookback Window to use and defining the Product Match for both Post-Click and Post-View conversions.
Lookback Window: The Lookback Window is the eligible time period between a sales transaction and an ad event.
Product Match: A Product match is the relationship between the purchased product and the advertised one.
You can also edit the Campaign Name, and Campaign Budget as per your requirements.
4. All set: Click Apply and your campaign edits will be applied.