Trying to configure Energy dashboard with solarman and volkszaehler

Hi,

i am new to HA and just wanted to implement my solar panels (connected to deye) and my currenty energy consumption to use the energy dasboard.
The deye data are already implemented via Solarman, but for the active power pdoduction it seems that i need to add a custom sensor:

- platform: template
  sensors:
    solarproduktion:
      value_template: "{{ states('sensor.solarman_total_ac_output_power_active') | float / 1000 }}"
      unit_of_measurement: kWh
      device_class: energy

With that code this sensor is shown in energy config and value shown in kWh.
For my current consumption i have Volkszaehler running and i have defined it like:

- platform: volkszaehler
  host: 192.168.178.83
#  scan_interval: 60
  uuid: "3eb235c0-7fbb-11ed-8559-3922369e5453"
  monitored_conditions:
    - consumption
    - average
    - max
    - min

Its added to HA, but the values differ from the values i am currently collecting via FHEM. Any idea why this is the case?
Furthermore i needed to configure customize.yaml to get it shown in the energy config page:

sensor.volkszaehler_consumption:
  device_class: energy
  unit_of_measurement: "Wh"
  state_class: measurement
  scan_interval: 60

Even if the sensor.volkszaehler_consumption is showing wrong values they are not shown in the energy tab.
Energy tab is configured like:

{
  "version": 1,
  "minor_version": 1,
  "key": "energy",
  "data": {
    "energy_sources": [
      {
        "type": "grid",
        "flow_from": [
          {
            "stat_energy_from": "sensor.volkszaehler_consumption",
            "stat_cost": null,
            "entity_energy_price": null,
            "number_energy_price": 0.3
          }
        ],
        "flow_to": [
          {
            "stat_energy_to": "sensor.solarproduktion",
            "stat_compensation": null,
            "entity_energy_price": null,
            "number_energy_price": null
          }
        ],
        "cost_adjustment_day": 0.0
      },
      {
        "type": "solar",
        "stat_energy_from": "sensor.solarproduktion",
        "config_entry_solar_forecast": null
      }
    ],
    "device_consumption": []
  }
}

Does anyone have a hint for me how i get it working?
Thanks,
Tobi