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Why do I get a warning message when listing an item using <BrandMPN>?
eBay keeps a large catalog of stock listing information (products). The product contains partially filled out Item Specifics and other descriptive information from a catalog—collectively known as product details. Using product details gives sellers a faster way to fill in Item Specifics and other information about an item. Many sellers may want to take advantage of products in order to quickly list items.
However, from time to time, users may encounter errors when using the eBay catalog in the AddItem family of calls (including Large Merchant Service, AddFixedPriceItemJob). It may be advantageous for sellers and developers alike, to have the best quality of data in the eBay catalog. If you encounter errors or incorrect information regarding any of the products in eBay's catalog, please report them via the feedback feature on this Knowledge Base article, https://ebaydts.com/eBayKBDetails?KBid=1939.
When listing an item you recieve a warning pertaining to BrandMPN.
<LongMessage>Multiple products found for <BrandMPN>. Product found for ProductReferenceID <Brand, MPN>.</LongMessage>
<LongMessage>No product found for ProductListingDetails.<BrandMPN> <Brand, MPN>.</LongMessage>
(There will be actual values in the <Brand, MPN>)
If you recieve either of these warnings please follow this article, https://ebaydts.com/eBayKBDetails?KBid=1829
Answer Title: Listing items with product information using eBay catalog
Answer Link: https://ebaydts.com/eBayKBDetails?KBid=1829
Answer Title: FindProducts support for MPN
Answer Link: https://ebaydts.com/eBayKBDetails?KBid=1723