Image files blueprint isn't used

I have a cover field in my pages->article blueprint that provides the possibility to select only one image out of the used images in the article (or another one that can be uploaded) which looks like this:

          cover:
            label: Artikelbild
            type: files
            max: 1
            multiple: false
            layout: cards
            translate: false
            template: image
            query: page.images
            accept:
              type: image
            image:
              cover: true
              ratio: 16/9

I have a image.yml in my files blueprints which looks like this:

# Each file blueprint must have a title, the title may be different from the file name
title: Image

# Like page blueprints, file blueprints can define a layout with tabs, columns, sections and fields
# File blueprints define what sort of information should get stored in a file's meta data file
# In addition to the fields defined in this example blueprint, you can also set what type of file is acceptable
# when this blueprint is used, which allows you to control what users can upload.
# More about file blueprints: https://getkirby.com/docs/reference/panel/blueprints/file

accept: 
  type: image

columns:
  - width: 1/2
    sections:
      content:
        type: fields
        fields:
          caption:
            label: Caption
            type: textarea
            size: medium
  - width: 1/2
    sections:
      meta:
        type: fields
        fields:
          alt:
            label: Alternative Text
            type: text
          photographer:
            label: Photogapher
            type: text
            width: 2/3
          license:
            label: License
            type: select
            width: 1/3
            options:
              - Unsplash
              - CC BY 4.0
              - CC BY-SA 4.0
              - CC BY-NC 4.0
              - CC BY-ND 4.0
          link:
            label: Link
            type: url

Now the problem is that an image (in my test case a simple jpeg) will be opened by the files->default.yml instead of the image.yml.
Why is that and how can I fix it?

The accept prop must be in the image blueprint.

There is no template prop for the files field, check out the right syntax in the docs:Files | Kirby CMS

Thanks a lot, I got confused by Can't select file blueprint - #2 by texnixe

Yes, files sections and files fields work differently, and the example you linked to is a files section.