Airtel monthly bills even after cancelling connection. And no responce even after repeated calls

I have taken airtel mobile connection(9945463653). and then given a request for disconnction becaose it does not have signal at my house.
I gave the request for mobile disconnection and have got the recipt of diconnection and I was suppose to get back my deposite back. but insted cancalling my connection Airtel keep sending me bills. I kept calling the airtel representatives and they said it will be taken care. but insteadnothing happened and they kept sending me the bills.

I have mailed the customer care too. but got no responce after one or two replies.

this is highly inefficient from airtel part.

And finnaly they send me a notice to appear to the court, it seems airtel does not want to pay me back my deposite and they started asking me mothly rents of mobile phone which is disconnected. and there staff does not follow when we speak to them.
I have all the communications mails and the recipt of request about disconnection request.

Please take a note of this how can ask me come to court when this foult is of airtel staff.

Can i file a complaint of humilation against the Airtel for this act??