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I listed an item by passing the ProductReferenceID. The item got listed but I received the following warning. What does this mean?
<ShortMessage>This product belongs to a different category, so the category has been changed.</ShortMessage>
<LongMessage>This product belongs to a different category, so the category has been changed.</LongMessage>
If you don't specify a category when you list with ProductListingDetails, eBay selects a category for you. But if you do specify your own category (or categories), the category needs to be mapped to (compatible with) the catalog for the specified product.
When you include product details in your listing by using ProductListingDetails, and you specify an incompatible PrimaryCategory, eBay resets the category to one that is mapped to the catalog and returns a warning in the API response. This change fixes cases where listings were failing with a blocking error when the category did not match the product identifier specified in the request.
As more than one category can be mapped to the same catalog, eBay is not always able to determine which category most closely matches your listing's product. Therefore, if eBay resets the category for you, we might list the item in an "Other" category. For example, a keyboard product might be listed in "Other" instead of "Keyboards". If this occurs and you want to change the category, you can use GetCategory2CS to determine which categories are mapped to the catalog that eBay selected, and then revise your item to specify one of those categories instead.