Fieldset factory does not triggered

Questions Components & MVC
1

Hello,
I can not inject my dependencies using a Factory with Fieldset because it looks doesn’t triggered.

My module.config.php

'form_elements' => [
    'factories' => [
        Form\Fieldset\MyFieldset::class => Form\Fieldset\MyFieldsetFactory::class
    ],
],

And my form:

namespace Application\Form;

use Laminas\Form\Form;

class ProfileBillingForm extends Form
{
    public function __construct()
    {
        $this->add([
            'name' => 'my_fieldset',
            'type' => MyFieldset::class,
        ]);

        $this->add([
            'name' => 'submit',
            'type' => 'submit'
        ]);
    }
}

MyFieldset::class in my Form doesn’t call the Factory (even it doesn’t exist yet)
What am I doing bad?

2

How do you instantiate your form? Via new ProfileBillingForm()?

3

A little bit of reading on the subject: