I am sure, i have warning 15 with ⚠ symbol, it‘s not error.
Half effect current sensor L18P040D15 sense PV current. By datasheet sensor output range is 0.04 to 4V. I aplied 1 volt to current sensor output to simulate a higher PV input current, and i see, that inverter reporting current correctly, it depends from current sensor output range. For example, aplied 1 volt on current sensor output reporting on inverter 6,7A PV current (see below).
So, on inverter PV input is real 280 volts, on PV current sensor i simulated 6,7A. Inverter see 276V and 3 ,6kW load (276Vx6,7A=1,8kW), but Warning 15 is still present.
Here video with no any load, PV input 276V, Battery 50V
Here video with PV input 276V, Battery 50V and simulated PV load 6.7A
My inverter is with PV charge controller 120-450V and 48V Battery.