Fibaro Outlet negative readings when high usage

For a few years now, I have been using the Fibaro Walli Outlet to change my PHEV.

Today I got a new charger that can handle 16A. The previous was 12A

I always collected the data from the sensor:

sensor: sensor.smart_outlet_phev_electric_consumption_w

But now, when the value gets over around 2900, 3000, it starts measuring in negative values.

Why does this happen or how can I fix this?

Anyone?
Where can i place a bug report about this?