A to Z claim granted even we didn't get the product

For my Order ID 702-7486603-4323400; customer returned the item and couple days ago, he opened an A to Z claim to get refund. But our warehouse said us that they didn't get the product yet. So in de appeal, we said we don't have the item yet and requested the tracking id, like Amazon suggest us to do. But after that Amazon granted in favor of the customer and even we write an appeal again, we didn't get any explanation.

If the customer forward you the tracking number, why you didn't forward it to us? If he didn't, why you granted the case in favor of the customer? We request you an explenation about that from you an we beleive at least this is our right @Ricardo_Amazon @Sunnie_Amazon @Jurgen_Amazon @Christine_Amazon @Lucre_Amzn @Daryl_Amazon