“Good day. I understand, but currently raw materials cost are keeping mark up, the product costs are raising sharply too. It's difficult for me to extend the product price validity. the sooner to send deposit, the better to enjoy old price. So in order to protect your business, we really need you assistance to arrange advance payment ASAP. So that we can order raw materials in advance to avoid increasing costs. hope for your understanding and awaiting for your valued reply.”