Images appearing multiple times in Media Library

I'm using Echo Rss Feed Post Generator to pull in the latest articles from our business news site (https://businesscrack.co.uk) onto our main news site (https://cumbriacrack.com). We have a box of stories from Business Crack on the Home page of Cumbria Crack and clicking on the story will take the user from Cumbria Crack to the Business Crack - the idea is to drive traffic to the business site - and this is all working well. The issue that we are having is that each time the RSS import is run (every 6 hours) a new version of any images is being created in the media library. So when I look at the media library I can see the same image multiple times. I've checked the image folder and there is only one version of the image, and this seems to have the latest import date/time. It's the fact that the image seems to be registered in the media library multiple times that is the issue - and it's very confusing for the journalists. How can I stop this? Is there a setting I've got wrong.   Thanks   Stuart