How do I reset the MMI touchscreen in an Audi Q7?

I am having trouble with the MMI touchscreen in my Audi Q7. It is frozen and not responding to any touches. I have tried restarting the car, but that did not fix the issue. How can I reset the MMI touchscreen?

To reset the MMI touchscreen in your Audi Q7, press and hold the MENU button, the central control knob, and the top right button at the same time until the MMI screen goes blank. Then release all three buttons and wait for the MMI system to restart.

You can also try resetting the MMI touchscreen by disconnecting the car's battery for a few minutes. This will reset all systems in the car, including the MMI system.