This error is commonly referred to as a “single matching error” and occurs when your Product ID (UPC, EAN, JAN, ISBN, etc.) corresponds to the Product ID of an existing ASIN; that is, some of the information you’re submitting contradicts the product information (title, brand, color, size, etc.) that is already present for that particular ASIN.
The provided SKU [SKU] conflicts with the Amazon catalog. The Standard Product ID value(s) provided for this SKU corresponds to the ASIN [ASIN]; however, some information is in conflict with the Amazon catalog. Following are the conflicting attribute values(s): Brand (Merchant: [MERCHANT_VALUE] / Amazon: [AMAZON_VALUE]). If your product is this ASIN, modify these attributes to reflect Amazon catalog values. If your product is different from this ASIN then check if the Standard Product ID value(s) are correct.
If the information in the Amazon catalog for this product appears to be incorrect, contact Seller Support.