Bsnl Bharat Sanchar Nigam Limited - Not getting back the security deposit from BSNL

I have applied to redeem the security deposit of Rs. *,***/. against my telephone number, on *.*.**. Also it was mentioned in the application, to redeem the credited amount of Rs. *,*** /- from the balance amount from Rs. **,*** /- which was paid in advance for my telephone number xxxxxx, and credited via BSNL invoice number EDCWBC*********, date *.*.** against the account number **********. I regret to inform you that, it is more than one year is over, but still I did not hear from BSNL regarding returning the money with the interest (as applicable) to my bank account. Last I heard from them one year back that, my application for security money have been approved, but because of the fund shortage they are unable to release the money.