Just coming back on this thread to share the following, it might help someone else. Having tried a few different methods that I found online, the following worked for me for a VW Polo 07.
Turn the engine off and take keys out.
Press and hold the button below the speedometer.
Keep holding, and put keys in and turn on (but don't start the engine).
Release button, then turn it to the right and hold (as if adjusting the clock minutes).
Hold until the display resets
Release the button and remove your keys.