BSNL nic service — still receiving the monthly bill

Address:

Khordha, Odisha

Sir,
My internet service has been disconnected from the month of July 2010 because of non payment of dues and I had also not received any bill from that month onward's. I thought that the amount might have been deducted from the security amount that i had deposited earlier, so i didn't go for further enquiry.
But all of a sudden the bill has been despatched in this month of august 2011 and all the due has been mentioned for the month's for which i had not received any service
( Till date ). I had went to the office and put forward my queries regarding the monthly bill but they didn't sort my problem.
Hence please suggest me some solution's to sort the problem.
Arjun