Airtel — not able to speak to customer care1

The network of Airtel in Chennai is worst.. Always getting connection errors.. tried speaking to any customer care team.. the call itself is not going.. I'm a postpaid customer for 10 long years, and service has never been poor like last 1 year.. whom should we complain and how to solve this problem.. Everyone in Chennai have this same problem.. most of the calls not connecting.. when we are in the middle of a call, the call is getting disconnected.. who takes responsibility for these uncomfortable situation faced by many.. when they don't have a welcoming customer care, what is the point in having their licence active.. I lost a major business because of these issues..