Non Repair / replacement of AC

I Purchase one window AC in month of April’14, from the 1st month AC has problem, in past 3 months ,, i used AC only for 10-15 days due to frequent problem in his functions.
i logged a complain in july month for repair of AC 3rd time, but after finish of july month there is no respond from the company, everyday i call to customer care, but there is no response at all from their side.

please help me either in repair of AC or replacement.

Regards
Kunal