Sometimes campaigns can encounter issues during publication and, we may need to investigate if the error returned isn't clear. In these cases you will receive a note from our team letting you know we're looking into the campaign.
If you're no longer interested in having that campaign published, you can just delete it from your dashboard. Navigate to your All Campaigns page, filter for Failed campaigns, check the box on the left of the campaign to select it, and then click Delete (trash bin).