The touchpad, is more than just a tablet.Its got all the other brains in it. It is what all the wireless sensors, the camaras, etc talk directly to. It is what has the sim in it for the fail over service. You technically could use a tablet, old phone, etc as a secondary pad device for unlocking and other things. it would just talk to the main pad.
I would try rebooting the pad first.
You can do it through the services menu I think..
If not, you will have to un plug it, and also pull out the battery. Hopefully a reset will fix it.Trying to remember.. if on the tablet part.. if there is a volume up/down button on it.. maybe it was turned down?
All that failing.. get them to send a tech out. The tablet is 'rented' with the service and not owned, so they can just swap it out and re connect everything.