Hello, I am a pacifier who loves infinity. I hope I can help you. You said your USB plug-in computer didn't respond. Maybe you deleted the system files that came with your mobile phone by mistake. Can you turn it off? You can't force itunes to close when you turn on your phone and connect to your computer. Press and hold the home button, and don't put the white Apple interface. Release the home button and don't put it on itunes. It will show the iphone being restored, and then it will be fine.