I just got this phone a couple weeks ago, and it as worked fine up until now. I held the power button on the side to turn it off, and the menu came up asking if I wanted to enable silent mode, enable airplane mode, or turn off phone. It is frozen on this menu now even though I selected turn off phone. Eventually the light turns off and I can't even turn it back on with the power button. When I plug it in, the icon at the top shows it's charging and the clock shows the right time, but the menu is still frozen there. What should I do?