Bharat Sanchar Nigam [BSNL] — not received refund

Address:	Vadodara, Gujarat
Website:	www.bsnl.co.in.

We are located in vadodara. We have stopped using bsnl landline services since 2017 n we have submitted all the accessories. We have completed all procedures regarding closure of services.
But since 3 years we have yet received our security deposit which is 3000.
We have been juggling here n there.
Last time when we visited them, they said that bsnl has no money to give.
My father in law, who is a senior citizen, has made several such visits in vain.
Please help us to get our money back.