Individual device shows no value in Energy Dashboard

Hi All,
My integration sensor

- platform: integration
  source: sensor.freezer_plug_power
  name: freezer_plug_energy
  unit_prefix: k
  method: left
  round: 2
  unique_id: sensor.freezerplugenergy

it has also been customized (customize.yaml) even if I think it is redundant:

  device_class: energy
  unit_of_measurement: kWh
  state_class: total_increasing 
  last_reset: '1970-01-01T00:00:00+00:00'

The problem I have is that it shows no data in the Energy dashboard (also waited the recommended 2 hours) :

despite the fact sensor shows data in the historical stats:

or Developer tools:

I have also searched the log for errors related to dashboard, this sensor… and found no indication.
What am I missing here?
I appreciate any suggestion.
Thanks in advance