My keyboard is completely unresponsive. I can move the mouse but none of my keys will work.. I have not used the laptop in...

Depending on how long you have owned your computer, it is common for a computer to slow down with the more information you are storing on your device. Music, pictures, and anything else that you have saved onto your Dell laptop takes up storage. The more item you have stored will cause the computer to slow down. Try deleting unused items off your computer and see how your computer responds to that. Also take a look at our troubleshooting page for more information about the device becoming slow at Dell XPS 15L502X Troubleshooting