I would express it less confrontationally. You reveal very little. So we can only speculate. The shared diagrams suggest a night setback or shutdown in the control of your heat pump. Since we don’t know how much knowledge you have (and 10kWp photovoltaic + 25kWh storage, as well as hot water with heating element, rather indicate little knowledge), here is an explanation again: We do not mean that you turn down all the thermostats in the rooms at night, we mean a central function stored in the control of the heat pump, which can possibly also be adjusted there. So if you name your system more specifically, maybe someone will make the effort to take a look...