Unable to save a light colour in a Scene

Configuration Frontend
1

I am trying to create a Scene, in which I want to save a Meross light bulb’s colour to be purple to alert me when the washing machine is done. But I can’t seem to “save” the colour within the Scene. If I create the Scene, save it, add it to my dashboard, change the colour to white via a different dashboard element then toggle the Scene to “on” the light remains white.

Might it be a limitation of the bulb itself, the integration (Meross), or perhaps me? (The code below is for a sort-of-purple colour).

TIA

- id: '1712759030313'
  name: Washing Machine Alert
  entities:
    light.dining_room_meross_main_channel:
      min_color_temp_kelvin: 2000
      max_color_temp_kelvin: 6535
      min_mireds: 153
      max_mireds: 500
      supported_color_modes:
      - color_temp
      - hs
      color_mode: hs
      brightness: 252.45
      color_temp_kelvin: 6391
      color_temp: 156
      hs_color:
      - 286.891
      - 93.333
      rgb_color:
      - 203
      - 17
      - 255
      xy_color:
      - 0.317
      - 0.125
      friendly_name: Dining room lamp (msl120d) - Main channel
      supported_features: 19
      state: 'on'
  icon: mdi:washing-machine-alert
  metadata: {}