Why my Migration don't reckognize my plugin in drupal 9

Question

I'm new in drupal and I try to migrate the article of an old blog with sql database to my drupal 9 project. I follow the instruction give by the drupal API migration docs, so i connect the 2 database in the settings.php. Then i generate a module with drush call article_migration the file migrate_plus.migration.article.yml :

#Migration metadata
id: article
label: migrate list of articles
migration_group: article_migration

#Source plugin, id defined in the @MigrateSource annotation
#in the src/Plugin/migrate/source/Article.php file.
source:
  plugin: article

#Destination plugin
destination:
  plugin: entity:node

#Process plugin
process:
  # Node type (bundle)
  type:
    plugin: default_value
    default_value: article

  # One-to-one field mapping using the default "get" process plugin.
  title: title
  body/value: content

  #Nothing needed here, it is a single table without any other relation.
  migration_dependencies: {}

plugin source article.php follow the norme :

/**
 * @file
 * Contains Drupal\article_migration\Plugin\migrate\source\Article
 */

 namespace Drupal\article_migration\Plugin\migrate\source;

 use Drupal\migrate\Plugin\migrate\source\SqlBase;

 /**
  * Source plugin for Articles
  *
  *@MigrateSource(
  * id = "news"
  *)
  */
  class Article extends SqlBase {
    /**
     * {@inheritDoc}
     */
    public function query(){
      $query =  $this->select('news', 'n')
        ->fields('n', array(
          'id',
          'title',
          'content',
        ));
        return $query;
    }

    /**
     * {@inheritDoc}
     */
    public function fields(){
      $fields = array(
        'id' => $this->t('Autoincrement ID'),
        'title' => $this->t('Article name'),
        'content' => $this->t('HTML content'),
      );
      return $fields;
    }

    /**
     * {@inheritDoc}
     */
    public function getIDs(){
      return [
        'id' => [
          'type' => 'integer',
          'alias' => 'n',
        ],
      ];
    }
  }

and yet when i try to execute the migration i have that message error that i don't understand saying that my plugin article doesn't exist :

The "article" plugin does not exist. Valid plugin IDs for Drupal\migrate\Plugin\MigrateSourcePluginManager are: news, d7_block_translation, d6_block_translation, block, d7_block_custom_translation, d7_block_custom, d6_box, d6_box_tra
  nslation, d7_color, d7_comment_entity_translation, d7_comment, d6_comment, contact_category, contact_settings, d7_view_mode, d7_field_instance_per_view_mode, d7_field_instance_per_form_display, d7_field_option_translation, d7_field,

if someone can put lead me to the right direction or tell me what i'am missing