Apexcharts-card dynamic colors

I’m trying to make the color change dynamically on a apexcharts-card radialBar.
In order to do that I use this template:

sensor:
  - name: PM2_5 AQI Color
    unique_id: e415238b-cc6d-4aa5-a894-0e83cbd0a7ed
    state: >-
      {% set pm2_5 = states('sensor.voorhaven_haren_belgium_pm2_5') | int %}
      {% set r, g, b = 0, 0, 0 %}
      {% if pm2_5 < 50 %}
        {% set r = 255 %}
        {% set g = (5.1 * pm2_5) | int %}
      {% else %}
        {% set g = 255 %}
        {% set r = (510 - 5.1 * pm2_5) | int %}
      {% endif %}
      {% set hex_color = '{:02x}{:02x}{:02x}'.format(r, g, b) %}
      {{ '#' + hex_color }}

Testing the template looks fine:

But using this code for a radialBar:

type: custom:apexcharts-card
header:
  show: false
  title: AQI
  show_states: false
  colorize_states: false
chart_type: radialBar
series:
  - entity: sensor.voorhaven_haren_belgium_pm2_5
    name: PM 2,5
apex_config:
  plotOptions:
    radialBar:
      offsetY: 0
      startAngle: -130
      endAngle: 130
      hollow:
        size: 50%
      dataLabels:
        name:
          show: true
          offsetY: -10
        value:
          show: true
          offsetY: 0
          fontSize: 26px
          fontWeight: 500
          color: white
        total:
          show: true
          offsetY: 0
          label: AQI
          fontSize: 12px
          fontWeight: 500
          color: white
          formatter: |
            EVAL:(w) => {
              return w.globals.series[0] + '';
            }
  fill:
    colors:
      - "{{ states('sensor.pm2_5_aqi_color') }}"

Only gets this:

Is there something wrong with this approach?

I do not think templates are supported by this card.