Scene brightness works only on second scene change signal

Hi all,
I have Tradfri lights attached to various scenes in my living room.

When changing from one scene to another, for some reason the brightness of the lights is not adjusted at first, but the color and color temperature are.

Only on the second time one clicks on a scene to activate, do the lights also adjust their brightness.

Am I doing something wrong? Scene definition below.

scene:
  - name: Living Room Daytime
    entities:
      light.living_room_ceiling_lights:
        state: on
        kelvin: 3500
        brightness: 255
        transition: 1
      light.color_light:
        state: on
        kelvin: 3500
        brightness: 255
        transition: 1
      light.reading_light:
        state: on
        kelvin: 3500
        brightness: 255
        transition: 1

`