Looking forward to a positive response.
With Warm Regards,
Write a Suitable Reply in Your Capacity as the Dealer of (Company Name)
The Finance Manager,
In reference to your letter ____________ (Date). I would like to intimate your good self that since the beginning of our business, this has been the first time that our payment has delayed. As you are also aware of the slump in the market, we will request you to give us some more time for the remittance of your payment. Your payment will reach you by ____________ (Month) end.
Your kind consideration in this matter will be appreciated.