Duplicate listings can be a serious issue for businesses, not only do potential customers struggle to find you, search engines receive mixed signals. DirectFeed submits the listing to the core data providers, and the providers have their own process to eliminate duplicate listings.
According to Moz -
"In the duplicate listing scenario, you never know which of your listings will outrank the others. You may end up with a highly visible listing with an outdated address, a wrong phone number or other issues showing up for your searches instead of your approved, authoritative listing. New customers may be misdirected by the bad data, causing you to lose business.
Your review equity may be split up amongst the different listings. Instead of having a single profile with 20 great reviews, you may have one listing with five reviews and another with 15. If the listing with only five reviews is the one that shows up, the great reputation you are building will be invisible to your potential customers.
Major search engines like Google will not know which of your listings to trust, whether within their own index or within other indexes they rely on for data. You always want to send a single, clear signal about your business to the search engines from each place it is listed.
Because of the way that data is fed from one local business index to another on the Internet, even one duplicate listing with bad data can be replicated across multiple platforms. Old listings with incorrect information can end up creating new listings with duplicated errors."
Source: Moz - https://moz.com/learn/local/why-duplicates-matter