duplicate ads

I feel like a bit of an idiot tbh. I should have noticed this sooner. But I thought replies were just being funky due to the insane engagement. I have two tweets, identical. So I made a tweet and promoted it. But in Ad Manageer, I 'copied' campaign to test another ad group, and it didn't then...

I've scraped craigslist to email potential clients to my directory, but I find people have several pages with the same content in different cities. How can I take my list of craigslist urls and delete the duplicate content urls so I'm not sending these people multiple emails?