請求書の間違いの苦情：This is to inform you that recently there have been many mistakes in our billing・・・

This is to inform you that recently there have been many mistakes in our billing. Can this situation be rectified? In invoice 03476, which is for one MiniData model XYZ ink jet printer, you are charging us ¥34,500 for the item (not including shipping charges). Your most recent price list clearly states that the unit sale price for this item is ¥24,500, which means we have been overcharged by ¥10,000. In the second invoice, number 03485, which is for one ChiisaiData model ABC laser printer, you have charged us only ¥120,000 where your price list clearly states that the price of this item is ¥130,000. It thus appears that you have overcharged us by ¥10,000 for one item and undercharged us by ¥10,000 for the second item. Is this a billing error or have you had unannounced price changes for both these items. Please look into this situation and get back to me by return e-mail to let me know what the situation is. In the meantime, we are withholding payment on these two invoices. I am sure that you would agree that if a little more time, care and effort was made towards accuracy on the part of your accounting department, we would mutually benefit. Sincerely, Taro Yamada (Mr.) NCC Enterprises 1234 Okii Ana Street Yamahora, Afghanistan