Not providing proper service though billing for it

Location/place: Bangalore

Name of company/service: Tata indicom braodband services

I used a static IP from tata indicom braodband. I shifted place from marathahalli to malleshpalya and the static ip stopped working.
From last 6 months , I have lodged several complaints and the serviceman came. He simply could not resolve the issue and repeatedly sent to my home for resolution.
This month I am billed for the static ip usage. Everytime I tell the customer care about the problem, the raise a service request and close it without resolution. In this process, I have wasted lot of time and effort but nothing came fruitful.
On top of it , I am freshly billed for the service and getting ontime reminders for payment of the same!!
Either they should tell me that they can not provide service and return me the money for the period it remained non-functional and freshly should not charge until the issue is resolved.