Accuracy of the POW Elite 20A Smart Power Meter Switch?

I bought and installed this device to monitor the usage of my 6kw heat pump.
I ran the heat pump fir 5 hours and got a total usage of 2.5kwh.

My electricity company charges 25c per kWh…. 62c for 5 hours usage? This can’t be right.

Is it broken or am I misunderstanding something here?

Why wouldn’t that be right? The power of the heat pump 6kW does not mean that the power consumption will be the same, and in addition, the heat pump is not running all the time, it switches as needed.