After one of payment i didn’t receive installation yet.

Location/place: Pune

Name of company/service: Tata SKY

I have purchased TATA SKY HD+ from authorized tata sky site. As they said on the website, they install it within 24 hours, but it’s almost one month after payment i made, i just waiting for installation. I called 100 times to their call centers. They are just promising me about installation in 2 hours after call, but in actual they are not calling back.
Help me out here to get my money back. I don’t want tata sky now if even they are offering me it for free of cost…