Your controller may have lost power. Please follow these steps to turn it back on.
If for any reason your legacy controller loses power, you can turn it back on.
If your controller is recessed in the wall, please follow these instructions:
The power button is on the bottom of the tablet. The button is accessed through the small hole in the lower right portion of the controller trim piece. Press and hold the button until the Windows logo appears on the screen.
If your controller stands alone and is not recessed in a wall, use these instructions:
Use the smaller button closest to the front of the device is the power button - To initiate a reboot you have to press and hold the button for 10 seconds (10 Mississippi) or until the Windows logo appears on the screen.
If you have a newer Altistat:
Press the "Restart" icon on your screen. You may need to double tap the icon depending on your software version.