Validation uniqueness of multiple fields in form class

Hi, i trying validate uniqueness multiple field in form class. I based on https://forum.phalcon.io/discussion/15851/using-uniqueness-validation-in-forms-with-multiple-fields-and-sp but i failed.

I make that code, but i can't find where's problem:

use Phalcon\Validation\Validator\Uniqueness as UniquenessValidator;

class BundleUserForm extends Form
{
    public function getValidation()
    {
        $validator = new Validation();
        $validator->add(['quantity', 'bundle_id'], new UniquenessValidator([
            'model' => $this->getEntity()
        ]));
        return $validator;
    }

    public function build()
    {
        $field = new Numeric('quantity');
        $this->add($field);

        $field = new Select('bundle_id', $this->bundleRepository->find(), ['using' => ['id', 'name']]);
        $this->add($field);
    }
}

After execution some weird error occurs in log:

Parameter 'name' must be a string

Anbody had similar problem? Any sugestion will by nice!