if its anything like the "virtual pedal" in the Skoda, which it likely is given VW and Skoda share the same parts bin........u need to "break" the sensor by kicking straight.

if u see the pics below, it will give u an idea of how the sensor is positioned, normally, inside the rear bumper/diffusor.

Tailgate Kessy Issues-tailgate-trigger-01-jpg

Tailgate Kessy Issues-tailgate-trigger-02-jpg