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1. You have set a UPC/EAN attribute in Product Identifiers settings. In case the product you sell does not imply UPC/EAN (e.g. handmade, private-label) and you have Amazon approval for listing products without Product Identifiers, use one of the Product ID Override options.
2. You have created a Product Type for new ASIN/ISBN creation and assigned it to a Magento Variational Product. The Product Type assigned to Magento Parent Product will be applied to all the Child Products related to it.
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