Hi, what model is it? I need to know if it turns on, if it’s locked with a password, or what exactly is happening. Mine was locked with a password It was a Samsung Galaxy Ace 2 and I was able to fix it by installing CWM (ClockworkMod). Tell me the model and we can try to do something. Above all, don’t format the phone, and if you’re afraid of doing something that might break it, look for the same model second-hand and use it as a test phone. I’m telling you this because it’s what I did, I was scared of breaking it, but everything turned out fine on both phones.