Tata Teleservices (Andhra Pradesh) — non refund of deposit even after 5 months

Address:

Hyderabad, Andhra Pradesh

i used to have a landline of Tata Teleservices bearing No.[protected], at hyderabad while I was at Hyd. on march26th 2012, when i submitted a written request for cancellation of the landline I was told that I have to pay an amount of rs.540/- upto[protected] and to that extent I gave letter requesting them to deduct from my deposit of 1,000/- which was held with for so many years. I was using this telephone almost for the last 10 years.
suddenly i received a threatening mail from the company's advocate stating that they will move to court of law from criminal proceedings against me for non-payment of dues upto[protected].
Is it that much necessary for a corporate group to proceed like this? when my balance is held with them and no kind of telephone line working with me of their company?
In addition, when my demand monthly bill is late of payment by me they used to charge a minimum of amount Rs. 50/- on wards is used to be charged.
Then in my case have they not to pay for the default of non-refund of my deposit of Rs.460/-(deducting the due amount) for every month Rs.50/- onwards till the receiving of my residual of the deposit amount?
kindly arrange to settle amicably and arrange for the refund of my deposit along with the penalty.
thnks,
J.V.Swamy., 56-9-4, vakakotireddy street, Vidyanagar, Rajahmundry-533105. (east Godavari District), Andhrapradesh.