Consumer Redressal

I had been a loyal customer to tikona for 2 years. Despite poor connection issues, I had persisted as I had no alternate service provider in my area. Several complaints of mine were not addressed. One fine day, I had it enough and I decided to close the connection. I sent a mail to customer care. Despite my email, bills continued to be generated and now I have an outstanding amount of around 2500 rs. I dont want to pay this amount for the poor quality of service and the fact that some of this was generated after my request for account termination. I am being threatened for legal action as well. Please help..