TATA TeleServices - internet connection cancel but still they sending unused bill.

I am Lekhraj R.Hatwar ,before 3 month on dated 16/2/2012, i am forward the application for deactivation of tata photon No.(9225402229) in smrat Ashok Sq. office.but still it is not closed and i continuously receive the unused bill amount every month.

cancellation request record on 16/2/2012------paid amount Rs.1900/- (receipt number:-40352719)
Request No- 297544979
again I receive the bill on dated period(17/2/12 to 23/2/12) of amount Rs.210/- which I paid on 14 March 2012(Receipt no:- 41158857)
All formalities are complete but still they continuously sending bills.