When we parse the payout report there are some transactions that don't have an order number or SKU to match it to a transaction in HP. These transactions are considered unmatched transactions. In most cases it's most appropriate to match the transaction to the Account versus a specific product if you aren't sure which product the transaction belongs to.
Please note: Amazon sometimes lumps Inbound Shipping Fees into one transaction even if it's for multiple SKUs.
FBA Inbound Shipping Transactions: Amazon doesn't provide the SKU for those transactions that are associated with FBA Inbound Shipping. HelloProfit doesn't know what product to associate it with.