Kutchina / Bajoria Appliances — Service failure

My sparkling issues and knob is not working since the first month of purchase then on asking for the service but they never replaced nor provided the service.
Then again on lodging the complaint they deputed the new service technician who said that the company will send the defected product with a new replacement. This continued till long six months and im still awaiting for the same. Please help me. They’re deaf n dumb and they hardly even bothered to respond.