Can't get my Lovelace config to work

Configuration
1

Hey everybody,

some background info:
I’m André and I killed (one of the hdds died) my server running homeassistant, a file server, a bunch of docker containers, several virtual machines… without a proper backup. :scream:
Yes. That was stupid.
I replaced alle the harddrives and reinstalled everything (the “homeassistant supervised” variant on top of an Ubuntu server running docker) and yes, I’m doing proper backups now. :see_no_evil:

Now let’s continue with the actual problem:
I now installed HACS and tried to install some custom cards from there and keep running into trouble.
I installed the “Atomic Calendar Revive” card and created a second dashboard (“Test-Dashboard”) following the documentation here: https://www.home-assistant.io/lovelace/dashboards-and-views/
In my configuration.yaml, it looks like this:

lovelace:
  # Das erste Dashboard soll das automatisch konfigurierte sein
  mode: storage
  #Custom Cards etc.
  #resources:
  #  - url: /community/atomic-calendar-revive/atomic-calendar-revive.js
  #    type: module
  # Jetzt die yaml Dashboards
  dashboards:
    test-dashboard:
      mode: yaml
      title: "Test-Dashboard"
      icon: mdi:script
      show_in_sidebar: true
      filename: test-dashboard.yaml

Note that the “ressources” part is commented - I already tried it with and without this part and it keeps giving me errors.

My test-dashboard.yaml looks like this:

title: "homeassistant.ha7.lan - Where the good shit happens"

views:
  - title: main
    panel: true
    icon: mdi:home
    cards:
      - type: entities
        name: "Test"
        entities:
          - light.licht_deckenventilator_buro
      - type: "custom:atomic-calendar-revive"
        name: "Kalender"
        showProgressBar: False
        showMultiDay: True
        entities:
          - <nextcloud calendar>
          - <another nextcloud calendar>

The Dashboard only shows the light switch and here is the error message from the log:

Logger: homeassistant.components.lovelace
Source: components/lovelace/__init__.py:168
Integration: Lovelace (documentation, issues)
First occurred: 13:59:01 (1 occurrences)
Last logged: 13:59:01
Cannot register panel at test-dashboard, it is already defined in <homeassistant.components.lovelace.dashboard.LovelaceYAML object at 0x7ffb924df8e0>

So… What am I doing wrong? I used to have a calendar with the events of the next few days on my dashboard and would like to get it back this way.

Best regards,

André