Tata Sky — Set top box faulty and not replacing

Address:

Gurgaon, Haryana

I am Manoj Kumar, having Tata sky connection bearing subscriber id is [protected]. I am not able to recive the channels as my STB is non mpeg4. For this i contacted to customer care on mid Jun 2015, and they replied that your STB will be upgraded and will be delivered to you soon. but the problem was not resolved. again i contacted to customer care having compaint no ISKLEJK. but no response from Tata sky. please suggest what should i do.