XXX IRS:
Our company didn't understand the relevant policies for tax refund, which led to the failure to specify the product specifications and models when issuing invoices, which caused trouble to your work. We are deeply sorry for this. The name and specifications of the goods issued on our invoice are consistent with the outbound order and the actual goods. If there is any discrepancy, our company is willing to bear the corresponding legal responsibilities.
XX company (official seal)
year month day.