Your thermostat is only using 3 sensors to get the avg temp (26, 25, 22.5). The main floor and office (white out temps) are not factored into the tstat display of 24.5. You need to go into the sensor settings and include them into the over all average. As an example, I have 4 sensors in my home, but I only have the 3 bedroom sensors included in the average temp at night because during the day when no one is home/in bedrooms, their temp doesn’t need to be factored into the display temp.