In order to measure the power consumed by
each of the three UFH zones the power meters P need to wired in between the zones and the contactor C as I have drawn in my attached diagram.
The same holds for elsewhere in your home to monitor power consumption by each UFH zone. So you should revisit how the power meters have been wired in - I cannot do that for you because I can no longer open any attached images in previous posts.
The total power consumption of your home however is measured by two meters - you might have thought three were required. For a three phase three wire system only two meters are necessary; the total power consumption being the sum of the two readings. Blondel's theorem if you want to look it up. My second attachment shows how they are connected. Note how the two meters are both connected to the third line N/L3.
If there were three meters they would be connected as in the last drawing, one in each line and the meters then connected to a common star node. Simply by making one of the lines common to the power meters one of the three meters becomes superfluous and an economy can be made.
Blondel's theorem:
Blondel’s theorem | Power in Poly-Phase System | Electricalvoice - https://electricalvoice.com/blondels-theorem-power-in-poly-phase-system/