Micromax Informatics — Network problem

Address:	581329
Website:	micromax

Dear sir,
am facing the problem last 6 month. in my mobile am using dual sim. in that mobile facing network problem in both sim. some time the network will fail automatically after i have restart of switch off the mobile and again i have to start then the network will come. so i changed the same sim card to other mobile the sim will work fine. so i think its may be the OS problem and i flash the mobile and Installed OS in micro max service center. Now also the same problem is there. please give solution of my problem.