Set attribute on template cover

Hello,
I have a Shelly Wave Shutter in use! Unfortunately, this is displayed as two devices in external venetian blind mode. One for the position, the other for the slat angle.
I have now tried to make one device out of the two using a template. It’s probably very amateurish, but that’s all my current skills allow.
In principle, the whole thing works reasonably well. Only the current position is not taken over. The current_position attribute always contains 0.
I would probably only have to write the attribute current_position from the entity “cover.raffstore_wohnen_ost” to the new entity. Unfortunately, I can’t do that.

cover:
  - platform: template
    covers:
      cover_wohnzimmer_ost:
        friendly_name: "Raffstore Wohnzimmer Ost"
        unique_id: raffstore_wohnzimmer_ost
        open_cover:
          service: script.cover_wohnzimmer_ost
          data:
            modus: "open"
        close_cover:
          service: script.cover_wohnzimmer_ost
          data:
            modus: "close"
        stop_cover:
          service: script.cover_wohnzimmer_ost
          data:
            modus: "stop"
        set_cover_position:
          service: script.cover_wohnzimmer_ost_position
          data:
            position: "{{position}}"
        set_cover_tilt_position:
          service: script.cover_wohnzimmer_ost_tilt_position
          data:
            tilt: "{{tilt}}"
        value_template: "{{is_state('sensor.cover_wohnzimmer_ost', 'open')}}"
        icon_template: >-
          {% if is_state('sensor.cover_wohnzimmer_ost', 'open') %}
            mdi:window-open
          {% else %}
            mdi:window-closed
          {% endif %}

script:
  cover_wohnzimmer_ost:
    sequence:
      - service: "cover.{{modus}}_cover"
        target:
          entity_id:
            - cover.raffstore_wohnen_ost
  cover_wohnzimmer_ost_position:
    sequence:
      - service: cover.set_cover_position
        target:
          entity_id:
            - cover.raffstore_wohnen_ost
        data:
          position: "{{position}}"
  cover_wohnzimmer_ost_tilt_position:
    sequence:
      - service: cover.set_cover_position
        target:
          entity_id:
            - cover.raffstore_wohnen_ost_lamellenposition
        data:
          position: "{{tilt}}"

sensor:
  - platform: template
    sensors:
      cover_wohnzimmer_ost:
        unique_id: cover_wohnzimmer_ost
        value_template: >
          {% if is_state('cover.raffstore_wohnen_ost', 'open') %}
            open
          {% else %} 
            closed 
          {% endif %}

Can someone please help me?
Thanks already

Have you tried


position_template: "{{ state_attr('cover.YOUR_COVER', 'current_position') |float(0) }}"

That was easy! Thank you!