Bharti Airtel - Data speed very low

I have been an airtel postpaid customer for more than a year. I was satisfied with their data service in most part of the country, except for northern part of west bengal. The data speed just sucks here. Compared to vodafone which is giving me close to ** Mbps. Airtel is giving me * Mbps that too is not constant. I will attach screen shots of both service providers. And ask Airtel... why do you show fake advertisements when you cant even deliver close to what you promise. India’s fastest network?? Yeah right!!!