Google calendar attributes

I am a newbie to HA and find it quite good although still struggling with the syntax and nomenclature. I have found some information for google calendar integration on the forum and in the documentation. My first question which is similar to this forum post (I cannot view images as access is denied). My code in sensors.yaml is:

  - platform: template
    sensors:
      sean_message:
        friendly_name: 'Sean calendar message'
        value_template: '{{ states.calendar.XXXXXX.attributes.message }}'

and to show it in the front end in groups.yaml I used:

- sensor.sean_message

I get a badge but without requested information. Obviously I have missed something but cannot figure out what I have missed. The google calendar component is working as the following component is working in the frontend and when clicked on shows all the attributes for the next calendar entry:

- calendar.XXXXXX

Thanks,
Sean

When you test this in the template dev tool, do you get the expected result?

See “The dev tools are your friend” at:

Thanks, that helped. It was a typo and the tool identified it quickly.