Stopped because of unknown reason "null"

I’m stumped on this one. I have a script that was working, until it wasn’t. Now when I try to run it, I don’t get any errors, I just see this error in the trace.

Stopped because of unknown reason "null" at September 18, 2023 at 8:04:55 PM (runtime: 1.92 seconds)

My script is just something I use to shut things down and try to make my TV, Stereo and chromecast devices play nice.

Any tips on where I’d look. Here’s my script. Interestingly, it seems to stop at a different step each time so it’s not like any one integration seems to be causing it.

TIA

alias: Shut It Down
sequence:
  - if:
      - condition: state
        entity_id: media_player.stereo
        state: 'on'
    then:
      - service: media_player.volume_set
        data:
          volume_level: 0.5
        target:
          entity_id: media_player.stereo
      - delay:
          hours: 0
          minutes: 0
          seconds: 1
          milliseconds: 0
      - service: media_player.turn_off
        data: {}
        target:
          entity_id: media_player.stereo
  - service: media_player.turn_off
    target:
      entity_id:
        - media_player.deck_tv
        - media_player.white_chromecast
        - media_player.deck_wifi
        - media_player.living_room_chromecast
        - media_player.deck_speakers_ca
        - media_player.shedly
        - media_player.sony_xr_65a95k
    data: {}
  - if:
      - condition: and
        conditions:
          - condition: state
            state: heat
            entity_id: climate.samsung_ac
          - condition: time
            before: '21:00:00'
            weekday:
              - sun
              - mon
              - tue
              - wed
              - thu
              - fri
              - sat
            after: '07:00:00'
    then:
      - service: climate.turn_off
        data: {}
        target:
          entity_id: climate.samsung_ac
  - service: light.turn_off
    data: {}
    target:
      entity_id:
        - light.tl_kids_bedroom_light
        - light.deck_lights
        - light.shed_light
        - light.adams_lamp
  - delay:
      hours: 0
      minutes: 2
      seconds: 0
      milliseconds: 0
  - service: light.turn_off
    data: {}
    target:
      entity_id: light.tl_lamp
mode: single
icon: mdi:power