Starting in August, you will get warnings for incorrect MPN values, and from September onwards, all products in violation will get disapproved.
Common reasons for getting this warning are merchants using the MPN field with SKU values or some self-assigned values.
If you are a reseller, you can not self-assign MPN values.
The main reason for this issue is due to not knowing the difference between MPN and SKU.
SKU stands for “stock keeping unit” and — as the name suggests — it is a number (usually eight alphanumeric digits) that retailers assign to products to keep track of stock levels internally.
An MPN, or manufacturer part number, is a manufacturer-assigned, unique, alphanumeric value used to identify a product among other products from the same manufacturer.
How To Fix?
If a manufacturer has assigned a bar code, then submit brand, MPN (if available from the manufacturer), GTIN, and set identifier exists to yes.
If the manufacturer has not assigned a bar code, then remove the values brand, MPN, GTIN, and set identifier exists to no.