I am writing this letter to claim the payments with reference to our accounts for the month of April 2010, which shows a credit balance of $5000. I have been waiting for this amount for many days for which it cost me a project. Please go through the invoice (no. 461) enclosed with this request letter for payment and we have not yet received the amount with respect to this invoice. We are expecting you to clear this amount within one month and it will be helpful for us otherwise we will be charging interest at the rate of 5% per month.
Please ignore this invoice if you have already paid this amount. Thank you and looking forward to continue the business relations with you. Hope to hear from you soon.