Automation won’t run

I have the below automation to run a scene at around sunset but it’s not working.

Can someone advise where I may have gone wrong with the code please?

- id: sunset_master_bedroom
  alias: Sunset Master Bedroom
  - event: sunset
    offset: +00:15:00
    platform: sun
  - data:
      entity_id: scene.sunset_bedroom
      transition: 300
    service: scene.turn_on
  mode: single