Send them a legal notice to change the set it they refuse then file a complaint in the consumer forum.
A purchaser is required to be more vigilant and law cannot help those persons who remain silent/unvigilant at the appropriate time. What were you doing at the time of its purchase? Why didn't you noticed its name and warranty card when it was being given to you. Why didn't you demanded the assurances in writing? All these questions are very vital and you have no reply against them except that you blindly believed on the oral assurance. So no consumer complaint lies except as covered under warranty card.