Statistics-graph does not recognize any REST sensor statistics

I have a REST sensor that delivers data, these are processed in the statistics.
That works
However, “No statistics found” is displayed in the statistics-graph card.

/config/sensors.yaml

- platform: rest
  name: zaehler_kg3cum
  username: "admin"
  password: "admin"
  resource: http://singleb.....
  method: GET
  scan_interval: 60

- platform: statistics
  name: statistik11
  entity_id: sensor.zaehler_kg3cum

/config/customize.yaml

sensor.zaehler_kg3cur:
  state_class: total_increasing
  device_class: energy
  unit_of_measurement: Wh
  last_reset: '1970-01-01T00:00:00+00:00'

sensor.statistik11:
  state_class: measurement
  device_class: energy
  last_reset: '1970-01-01T00:00:00+00:00'
  unit_of_measurement: Wh

I have been working on this problem for 5 hours thanks for your support in advance.

If you are using Home Assistant 2021.9.x, last_reset: is no longer a valid attribute. Remove it from your customizations.

For energy sensors change the state class to total_increasing.

Thank you for the support (core-2021.9.3)

  1. Change
    /config/customize.yaml
sensor.zaehler_kg3cur:
   state_class: total_increasing
   device_class: energy
   unit_of_measurement: Wh

sensor.statistics11:
   state_class: total_increasing
   device_class: energy
   unit_of_measurement: Wh
  1. restart HASS
  2. Clear browser memory

Unfortunately no change

I made a really stupid mistake. /config/customize.yaml was not involved
Thank you for the support