BSNL
Security Deposit still NOT received

I have submitted the final documents with the request for Security Deposit cheque on 26.09.2011 at the BSNL office (Salt Lake).

I was told to contact them at a phone no. - 03323340304 if the cheque does not arrive at my address after two months.

As usual, it has NOT arrived yet. I have been contacting them at the above said phone no. but everytime they say that the cheque has already been dispatched but it is almost 6 months over and I HAVE NOT RECEIVED THE CHEQUE.