Hi! I've done the same thing (duplicate listings). It's an easy fix.
Sign into your ebay account, and find the listing you want to delete. Click on the drop-down menu to the right of the item and select "end item." The next screen, if I remember correctly, asks you to select from a list of reasons for ending the listing. Some of the options are duplicate listing, listing has errors, or item is no longer available. I never checked to see what ebay does as far as listing fees go.
I think we've all done this at one time or another Unless you ASK ebay to refund your fees (and they might not) you will pay for the ended listing. I've done this twice, once they credited me, the next time they didn't.
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