I've updated my Lumia 630 Dual sim from Lumia Cyan to Denim. The update was perfect and every thing has been fine at first. Later I made a call from one of the sim, but the call didn't connected. I haven't heard nothing from the phone. I tried to disconnect the call, but the call button freezes out. I could only restart the phone to be back normal. But after restart, soon I made the call and the call connected. After some time I tried to turn on the mobile data from the mobile+SIM and I couldn't find the button to turn on mobile data. The sim settings in the mobile+SIM has been greyed out. Again I need to restart to use the mobile data. The problem is, after restart, if the phone is idle for sometime the mobile+SIM setting is freezing. This problem came only after the update. Is there any way to resolve this? I tried soft reset. No way! Is there any way to contact Microsoft support to inform this problem and to ask for an immediate release of an update? Any help?