Viessmann Integration: How to reset Gas consumption sensors?

Hi there,
the Viesmann Integration provides sensors for heating and hot water gas consumption. This is perfectly fine because it works out of the box with the energy dashboard. But I want to reset these sensors (or derived ones) to zero, when I get my gas tank refilled (mostly once a year in the summer). My goal ist to calculate the amount of gas used in litres, so I can estimate when to refill the tank.