MQTT light Entity; brightness sets state to ON

Configuration
1

I have a light entity defined in MQTT:

- light:
    name: "Occhio Light Desk Left"
    unique_id: "occhio_light_desk_left"

    # ===== STATE =====
    state_topic: "casambi/0/get/poll_device/6/values"

    state_value_template: >
      {% set lvl = value_json.level | int(0) %}
      {% set last = value_json.last_level | default(0) | int %}
      {{ 'ON' if (lvl > 0 or last > 0) else 'OFF' }}
    #{{ 'ON' if (value_json.level | int(0)) > 0 else 'OFF' }}

    brightness_state_topic: "casambi/0/get/poll_device/6/values"
    brightness_value_template: >
      {{ value_json.level | default(0) | int(0) }}

    color_temp_state_topic: "casambi/0/get/poll_device/6/values"
    color_temp_value_template: >
      {{ ((1 - ((value_json.cct_level | default(0)) | int(0) / 254)) * (500-153) + 153) | round(0) }}

    json_attributes_topic: "casambi/0/get/poll_device/6/values"

    # ===== COMMAND =====
    command_topic: "casambi/0/set/target_level"
    brightness_command_topic: "casambi/0/set/target_level"
    color_temp_command_topic: "casambi/0/set/target_tc"

    # 🔆 Helligkeit setzen
    brightness_command_template: >
      {{
        {
          "level": value | int(0),
          "targetid": 6,
          "targettype": 1
        } | tojson
      }}

    # 🌡️ Farbtemperatur setzen
    color_temp_command_template: >
      {% set mired = (value | int) %}
      {% set m = [500, [153, mired]|max]|min %}
      {% set cct = (((500 - m) / (500 - 153)) * 254) | round(0) %}
      {% set level = state_attr('light.occhio_light_desk_left', 'brightness') | int(254) %}      
      {{
        {
          "level": level,
          "tc": cct | int,
          "targetid": 6,
          "targettype": 1
        } | tojson
      }}

    # 🔴 EIN/AUS über kompletten Payload
    #command_topic: "casambi/0/set/target_level"
    on_command_type: "brightness"
    payload_off: '{"targetid": 6, "level": 0, "targettype": 1}'
    
    brightness_scale: 254
    qos: 1
    optimistic: false

    device:
      name: "Casambi Gateway 0"
      identifiers: ["casambi_Gateway_0"]
      manufacturer: "Lithernet"
      model: "Casambi MQTT Gateway"
      sw_version: "4.56"

But it makes problems because the state of the entity will not switch off. That’s because of the payload_off definition. If I switch the luminaire OFF the payload_off command is send. An answer is send back so the level is set to 0. Because brightness will not be set to 0 (seems to be a function in home assistant) the brightness still have the last value. And it’s fixed inside homeasisstant that brightness > 0 the state of the entity is set to ON.

If I delete the payload_off definition the state is set correctly. But then other defined lights are switched off also because a broadcast is send to MQTT.

Does anyone have a solution for this problem?

Thanks a lot
Stefan