If your ad has not yet gone live, you can delete your campaign and the payment authorization you've placed will be voided.
You can pause an ad at any time. Navigate to the campaigns edit page and notice the blue buttons located on your campaign dashboard. Simply click pause!
Note: If your ad's performance is not up to expectations, try editing your creative before pausing or canceling the campaign. In the past, advertisers have updated a headline title or swapped out a thumbnail image to make the ad more enticing to viewers. Small edits can result in higher engagement and more clicks.