My daughter's Galaxy Ace won't boot up. She hasn't tried to install any type of custom ROM (she doesnt even know what they are). She was playing a game on it and the phone just froze. I have taken the battery out and then replaced it but now it goes to the "SAMSUNG ACE" screen, jumps to the "welcome to O2" screen and then sticks on a black screen with "SAMSUNG" on it. Every now and then it will go from that back to the O2 screen and then back to the Samsung screen. Any ideas how to get it back without wiping anything?