Mqtt automation "invalid platform specified"

Configuration
,
1

Hello,

I have the following issue with an automation that worked previously:

2019-11-05 01:45:33 ERROR (MainThread) [homeassistant.config] Invalid config for [automation]: Invalid platform specified @ data['trigger'][0]. Got None. (See /home/hass/.homeassistant/configuration.yaml, line 214). Please check the docs at https://home-assistant.io/integrations/automation/

Here is the relevant configuration code. Most of it was lifted directly from what the automation editor generates.

automation:
- alias: "Eingehender Anruf"
  trigger:
  - platform: mqtt
    topic: incoming_call
  action:
    - service: media_player.media_pause
    - service: notify.notify
      data:
        title: "Eingehender Anruf"
        message: "Anruf: '{{ states('sensor.incoming_call') }}"

I am at a loss what I’ve done wrong.

2

Okay. So this issue seems to go away after creating an empty automation.yaml file. This is strange.