IPhone 4s freezing when I try to unlock?

I have a passcode on my phone. Whenever I try to unlock it, after typing in the four numbers it freezes and doesn't open, still displaying the unlocking screen, if that makes sense. It's restarts itself after this happens, but the problem keeps happening. I have ios 6.

Get a new one or else take it to a repair shop and let them fix it

Mmm remove the Battery of phone then put it again but remove it after closing the mobile phone