An error like "XML Parsing Error at Line 1, Column 2986: cvc-complex-type.2.4.b: The content of element 'Clothing' is not complete. One of '{ClassificationData}' is expected."

Means that the item classification value for the product is required but missing, an example of this value would be the "ClothingType" value for "ProductClothing" - each Product Type, might have it's own name and accept values. Those should be stored in this knowledge base separately.