Changing product URL leaves a ghost duplicate product not picked up in inventory and with broken URL?

Site URL: https://www.externaldoorsonline.co.uk/

Hi

I am moving a product from one store to another so that I can duplicate for ease of creating a new product with a similar layout in a new store. When I change the URL from the original copied URL it creates 2 products. The 1st being the one Im looking to create with the new URL, the 2nd is a ghost product. It doesn't show in inventory but shows in the store. Clicking the item takes you to a broken link with the original unwanted URL.

Any ideas how to get rid of the broken link unwanted product thats not in product inventory?!