I created a module for flagging entities automatically when created or updated.

There are some errors in my code because only nodes work.

If a user "user1" creates a node, the flag will be in his name. I want the flag to be done automatically on behalf of the site administrator.

How do I get the administrator to automatically flag?

    use Drupal\flag\FlaggingInterface;
    use Drupal\Core\Entity\ContentEntityBase;
    use Drupal\user\Entity\User;
    use Drupal\commerce_store\Entity\Store;
    use Drupal\commerce_product\Entity\Product;
    use Drupal\group\Entity\Group;
    use Drupal\node\Entity\Node;
    use Drupal\comment\Entity\Comment;
    
    /**
     * Flag node.
     */
    function admin_task_notify_node_update(Node $node) {
        $flag_id = 'moderate_node';
        $flag_service = \Drupal::service('flag');
        $flag = $flag_service->getFlagById($flag_id);
        $flag_service->flag($flag, $node);
    }