Airtel — charged extra amount

Address:	560100
Website:	www.airtel.in

I was using airtel postpaid and they were providing 10 gb extra for every extra month but in the end they charged us for using those data which they provided for free
Moreover they charged me ₹470 for transfering from postpaid to preepaid they said extra amount will be refunded in your prepaid no. But nothing happen.
When i complain regarding this they said they will waffer me remaining amount in 7 days now it is 1 month and they are still making fake commitment that they will return the amount.
I am using airtel for last 8 years never had such a bad experience.
But i cann't take this anymore.