Write an email to your existing client who is not happy with your service and asking for refund where refund is not in your policy?

Dear Sir,
With regards to the mail which you have written to me some days back,I want to talk to you regarding the problem of the refund you are talking about.I really apologize for the problems that you have faced while availing to our service.I want to tell you that the cable connection line which we have installed in your house is working perfectly fine.But as you complained some days back that the picture quality in your television was not coming clear due to some loose wire connection,I am sending my engineers to your house tomorrow to do a quality service check of the whole wire connection.I understand that it had been almost one week when you registered you complain via email on our company's website,but no proper action was taken against your complain by our engineers.I will take stringent actions against the person in my staff who didn't bother to work on the complain which was registered by you.I would like to tell you that it is in our policy that we can't refund the money back after we have provided the service to our customer.I understand that you have paid this month's bill and the problem started from the beginning of the month only,but I am really sorry for the refund part due to the our company's stringent policy.

So,I assure you that we will definitely solve your problem.I regret for the inconvenience that caused to you by the bad quality of our service and hope that you will cooperate with us on this issue.That is the reason for me to send my engineers to your house as early as possible.I hope that the problem with your television will be identified as soon as possible.

With regards,
Nitish Thapliyal
Manager
Tolex Ltd.