Network problem in handset micromax p350

Location/place: Panvel

Name of company/service: Micromax

Dear sir/mam,
i purchese micromax p350 funbook phone on oct 2012 from panvel . And from day first this phone didnt catch network signal of any selluler company.
I rush to service centere at panvel and show them problem they told me that i have to change network provider ok i hv swap my network to vodafone, idea,and airtell but no change. Phone still not show any network enevn i cant call anyone.
Again i visit to service center this time they told me that every model of this phone series has same problem, we cant repaire it . Sir i have spend 7500rupes on this phone i want it get repaire or get replaced. I have origional bill and all comunication with service center in writen form .please guide me whether should i contact and get justise