Why is stock checker showing two listings from the same seller ?
Amazon allows merchants to list products using identifiers (FNSKU's) under the same ASIN, this causes an instance of what is called "double listing".
Take this ASIN for example: https://www.amazon.com/gp/offer-listing/B003UF0RB4/ . At the time of writing this, a seller named EversDirect is showing as a "double listing"
What is "double listing" ? Double listing is when a seller selling via FBA and sent in the products under different FNSKU. The product listing becomes active duplicating SellerID and creating two sets of inventory counts for this ASIN under this same sellerID.