Deposit Not Refunded

Location/place: Hyderabad

Name of company/service: Reliance BroadBand

I have taken a reliance broadband connection in September 2011 and disconnected the connection in February 2012. Till now they havent given the refund of the deposit money they took while installing the connection.Its been an year exactly. I have written mails to them many times but there is no response from them.They have collected their equipment immediately after termination but there is no action from their side about refunding the deposit money.