Repeater not shown in admin

// FormController.php
<?php

namespace ClickfoodBasicCms\Twill\Capsules\Forms\Http\Controllers;

use A17\Twill\Models\Contracts\TwillModelContract;
use A17\Twill\Services\Listings\Columns\Text;
use A17\Twill\Services\Listings\TableColumns;
use A17\Twill\Services\Forms\Fields\Input;
use A17\Twill\Services\Forms\Form;
use A17\Twill\Http\Controllers\Admin\ModuleController as BaseModuleController;
use A17\Twill\Services\Forms\Fields\Repeater;

class FormController extends BaseModuleController
{
    // .....
    public function getForm(TwillModelContract $model): Form
    {
        $form = parent::getForm($model);

        $form->add(
            Input::make()->name('description')->label('Description')->translatable()
        )->add(
            Repeater::make()->type('fields'),
        );

        return $form;
    }
    
    // ...
}

// resources/views/admin/repeaters/fields.blade.php
@twillRepeaterTitle('Field')
@twillRepeaterTrigger('Add field')
@twillRepeaterGroup('app')

@formField('input', [
    'name' => 'label',
    'label' => 'Label',
    'required' => true,
])

@formField('input', [
    'name' => 'handle',
    'label' => 'Handle',
    'required' => true,
])

@formField('select', [
    'name' => 'type',
    'label' => 'Type',
    'required' => true,
    'options' => [
        [
            'value' => 'text',
            'label' => 'Text'
        ], [
            'value' => 'number',
            'label' => 'Number'
        ], [
            'value' => 'email',
            'label' => 'Email'
        ]
    ]
])
 
@formField('checkbox', [
    'name' => 'required',
    'label' => 'Required'
])