Bharat Sanchar Nigam [BSNL] — bsnl landline refund of security deposit not received on repeated follow up

I had surrendered my land line no.[protected] on 12th june, 2019 at kasba rathtala exchange. On advice of the receiving official, i visited the ballygunge place exchange with the landline disconnection receipt and cleared all the dues till date. As directed, i provided the concerned official with my bank account details for credit of the refund of inr 2282 (As told to me by the concerned official) and the associated documents for the same. After that, i had followed up with them by visiting their office multiple times but they always came up with some excuses viz. The poor condition of bsnl company in recent times, bsnl employees' current woeful situation, the basic time required for the completion of the procedures, etc. Etc. Being a loyal customer for 25 long years of the government enterprise, i had expected the least courtesy from bsnl to return the security deposit to me at the earliest, to which i am legally entitled. Almost 1 year is going to complete since i surrendered my landline connection, but still clueless when i would be fortunate enough to receive my own hard-earned money. Please look into this matter as soon as possible. Your earliest action is highly solicited.
Regards
Tapati ghosh
Bsnl customer id: [protected]
Bsnl account no.: [protected]