mobile stolen from thane

IMEI NO 356785012479115

I bought an HTC Touch (3450) phone 3 days ago.It automatically shut down yesterday all of a sudden and now doesn't start!!? It doesn't even get charged anymore. There is nothing I can do... for this phone to come to life ! When I went to the dealer from where I purchased it, they said replacement from their side is only done within 48 hours. A brand new phone dies without any reason in 3 days and I now have to go to the service center to get it repaired! Please suggest a way to get it replaced by the manufacturer smb. I live in Pune, India.