If your screen is unresponsive a hard reboot should resolve the issue.
Please see below for details on how to hard reboot your Hub Controller.
Hard reboot with the black tool
Hard reboot without the black tool
Step 1
If you don’t have the ‘black tool’ at hand, you can use the top of a small screwdriver to push in one of the black release buttons on the image below.
Step 2
The left side of the device will disconnect from the back backplate and you can then remove it. Once you have it off you, just need to click it back on.