Class Does not exist

I am having the following error

InvalidArgumentException in FormBuilder.php line 39: Form class with name App\Http\Controllers\App\Forms\SongForm does not exist.

on Laravel,

SongsController.php class

<?php

namespace App\Http\Controllers;

use Illuminate\Routing\Controller as BaseController;
use Kris\LaravelFormBuilder\FormBuilder;

class SongsController extends BaseController {

    public function create(FormBuilder $formBuilder)
    {
        $form = $formBuilder->create(App\Forms\SongForm::class, [
            'method' => 'POST',
            'url' => route('song.store')
        ]);

        return view('song.create', compact('form'));
    }

    public function store(FormBuilder $formBuilder)
    {
        $form = $formBuilder->create(App\Forms\SongForm::class);

        if (!$form->isValid()) {
            return redirect()->back()->withErrors($form->getErrors())->withInput();
        }

        // Do saving and other things...
    }
}

SongForm.php

<?php

namespace App\Forms;

use Kris\LaravelFormBuilder\Form;

class SongForm extends Form
{
    public function buildForm()
    {
        $this
            ->add('name', 'text', [
                'rules' => 'required|min:5'
            ])
            ->add('lyrics', 'textarea', [
                'rules' => 'max:5000'
            ])
            ->add('publish', 'checkbox');
    }
}

routes.php

Route::get('songs/create', [
    'uses' => 'SongsController@create',
    'as' => 'song.create'
]);

Route::post('songs', [
    'uses' => 'SongsController@store',
    'as' => 'song.store'
]);

And I do not know where is the problem because the file exist in the project folder.

via Chebli Mohamed