updating lollipop 5.0.2 show ! mark on sim and H, H+ and E networks are not displayed

I have two sims Airtel and Docomo inserted as in Sim 1 and Sim 2 respectively. I restarted the mobile and checked but the ! mark does not goes and moreover when 3G is connected neither of H, H+ and E is shown. Another problem is that the network is not consistence. Every time the network goes for both the sim resulting in friends complaining as network not reachable. Please somebody help me with this and provide me the solution for this. Moreover i cant understand y these customer care people simply talk when they are not able to fix customers problem..