Micromax Informatics — totally disappointing with micromax service

I own a micromax canvas spark 3 phone q385 whose power button in the side panel has fallen off. Therefore it's becoming very difficult to switch the power on off of the phone. I had taken the phone to various centres and nobody could fix it. Finally, i was advised by micromax customer care to visit to lajpat nagar service centre. To mu utter surprise i was been told that the part (Side panel) is not available with micromax anymore. How can then micromax take the responsibility of servicing the handsets used by their customers. This is totally irresponsibility of the company. My phone is not even a year old and i have been running to get it fixed here there. Can micromax give me a suitable solution for this problem of mine?

Kasturi