Micromax — Cut of quickly

I bought a Micromax Canvas Fire 2 A104 from Dialogmobile, Thamarassery, Kerala on 7/11/14 and start using in U.K where I have excellent data connection and wifi but unfortunately if I play a video it only works few minutes and cut off.(lagging) If I reboot it will work again as same. Also the screen is hard (is that way ?) (imie [protected]) Can you pl help