催款通知书的英文

Dear Sirs,Account No.8756It is very difficult to understand why we have not heard from you in reply to our two E-mail of 8th and 18th September for payment of the sum US$ 80,000 you are still owing. We had hoped that you would at least explain why the account continues to remain unpaid.I am sure you will agree that we have shown every consideration and now you fail to reply to our earlier requests for payment, I am afraid you leave us no choice but to take other steps to recover the amount due.We are most reluctant to do anything from which your credit and reputation might suffer and even now we prepare to give you a further opportunity to put the matter right.We therefore propose to give you 15 days to clear your account,Yours faithfully,