是要写英文信件吧: Dear ***, Please note that we've got something wrong in the former order.In the first order we bought 5 pieces of parts and we paid the money of 10 pieces(with 5pcs overdrawn) according to your receipt.So what I want to say is:can we keep the 5pcs in the latter order for free charge,because we had paid the money? Would you please check and reply soon? Best regards