the voltage value is the phase voltage that the voltage between the live line and the neutral line.
The 380V should be the line voltage that the voltage between phase and phase.
Please let me know how do you install your energy meter, have you connected the neutral line?
The IAMMETER-cloud just shows the phase voltage in its dashboard now.
The voltage that displays in the IAMMETER system is all phase voltage.
Maybe we would consider providing an extra setting in the meter configuration later that let the user select whether to display line voltage or phase voltage.
The line voltage and phase voltage are two different parameters regards to the voltage.
The formula is line voltage = phase voltage * 1.732
We select to display phase voltage here which does not mean the line voltage is not correct.
The power result will not be affected by whether we choose to display line voltage or phase voltage here.