Xiaomi India — Network issue

Address:	147001
Website:	Mistore

I received my xiaomi 3 s 12/9/16 when I put the sim in this phone and on then not show network then I call customer care executive asked me software update but I try for software update its not update with WiFi (4g speed) and now I have no network connection in my 3s phone but another phone same sim have network.some software not opening. I have no another phone pls my this phone replacement urgently. I have purchase this phone mi store