Update index algolia

I have an index in algolia using Documents and the users associated with theses Documents

class Documents extends Model
{
use Searchable;

public function toSearchableArray()
{
  $data = $this->toArray();

  // formatting relationship for algolia

  $data['users'] = $this->types->toArray();
  $data['document_type'] = $this->typeDocuments->name;
  return $data;
}

protected $fillable = array('name', 'description', 'document_type');

public function types() {
    return $this->belongsToMany('App\Users', 'document_rights', 'user_id', 'id');
}

public function typeDocuments() {
    return $this->belongsTo('App\Document_type', 'document_type');
}
}

In my case, i will update one day, the name of the Users, like this :

  public function update(Request $request)
  {
      $user = Users::find(5);
      $user->name = 'jean floriot';
      $user->update();
  }

But it never changes the User in the index of Algolia. Any ideas how to proceed ?

i'm using Laravel 5.5 with Scout

via Chebli Mohamed