Laravel can no longer find my self-created commands

no matter what command I want to execute, Laravel responds with the following error:

There are no commands defined in the "dev" namespace.

It doesn't matter which of my commands I run. I always get the same error message, just with a different namespace

Thats my code of one command:

<?phpnamespace App\Console\Commands;use Illuminate\Console\Command;class dTest extends Command{    /**     * The name and signature of the console command.     *     * @var string     */    protected $signature = 'dev:test';    /**     * The console command description.     *     * @var string     */    protected $description = 'Command description';    /**     * Execute the console command.     */    public function handle()    {        $this->info("Test Command");    }}

My PHP-Version: 8.2.20My Laravel-Version: 11.8.0My OS: DebianMy Webserver: Apache

Does anyone have an idea where the error might be?

I created a new command for testing. This was done with the command

php artisan make:command --command=dev:test