Hathway Broadband Internet mumbai - Not providing the promised speed and connectivity

I am not being provided the required speed as promised to me by Hathway. Also I am facing a lot of connectivity issues . I have paid the Internet charges annually and still I am getting poor service. I have raised the complaint with them and also with their appellate authority but still it is not resolved . No service technician visits the house to inspect CPE (Customer Premise Equipment) for fault detection or does not call to acknowledge whether the issue is resolved or not . It has been over a month now and I am facing lot of problems due to this . I am working from home and my work depends a lot on internet but due to their poor customer service it is affecting my work.