Edit the feed list of the campaign and save it.
Removing a feed only changes future runs. Posts already published from that feed stay on your site.
Campaigns made by Auto Setup, named like Sports (Auto), are different. Change their feeds in the table Your categories and their RSS feeds on the Auto Setup page, then click Save & create campaigns. That button replaces the feeds of Auto Setup campaigns with the values from the table, so a change made only inside the campaign would be lost the next time you click it.
Tip: replace feeds that keep failing, rarely give photos or often get held by Logo Protection. See Map categories to RSS feeds.
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