I can't unlock my phone using the touch screen on my LG Cosmos Touch. Which means I can't access the calender, recent calls, and the other features on the phone. The only thing I can do is slide the phone when I need to answer a call or send a text. I'm not sure what the problem is. I also don't want to pull the battery out and re insert it because I think if I do that, my phone will lock up permanently. Will someone help me please?