Airtel — no indoor coverage for airtel

Address: Bangalore, Karnataka, 560037

I am facing lot of call drops because of very poor signal strength inside the house in a city
When complained to airtel they always say that they are working on the problem but never do they work
And one more dumb answer they give is that they tried to contact me but they could not connect. If there is no network signal at all at home, how can they contact me through call. They have to send a site engineer but they never did.