I am currently having problems with my iPhone. So it froze last night and went completely black. so I left it for a while, hoping it would un-freeze. then all of a sudden it turned off and I tried to turn it back on and no luck. So, I took the battery out (as the back was already coming off) and put it back in. And the only thing its doing now is the apple is coming up every time I put in on charge. I left it on charge over night and all day today but nothing has happened. What is the reason for this and how can I fix this?