Concorde Motors India Ltd - Non Refund of Security Deposit

We purchased a Tata Nexon Karz *.* Diesel from M/s. Concord Motors (I) Ltd., Prabhadevi Showroom, Mumbai now known as Puneet Automobiles Pvt. Ltd., in exchange of my old Skoda Rapid in the month of Oct – ****. They have kept of Rs. **,***/- as Security deposit until the RC transfer to new buyer.
RTO office issued the NOC for the RC vivid no-MH****-NOC****J on **/**/**** & the same submitted to Concord Motors worli office along with request letter for refund our deposit. That after providing the said NOC the company did not provide the security deposit of Rs.**,***/- till date. We have been following up with their Worli office since so many months; even we sent a many mails & reminders to Rishikesh Potdar - Concord Motor, Tata Motors customer care & Mr. Harsh Bhushan who is Maharashtra Region Territory Sales Manager regarding the said issue but they never bothered to resolve the issue till date. This kind of unprofessional created a mental pressure to me.
I request all be cautious while making a transaction with Concord Motors (I) Ltd. / Puneet Automobiles Pvt. Ltd. Worli, Mumbai.