Why is the file not loading from the form to the correct directory?

Question

Yii

There is a form with which the data is loaded into the database and displayed on another page. You need to add a file upload to the form.
The form

<?php

/* @var $this yii\web\View */
/* @var $name string */
/* @var $message string */
/* @var $exception Exception */

use yii\helpers\Html;
use yii\widgets\ActiveForm;
$status = Yii::$app->user->identity->status;
?>
<div>
<? if($status == 'admin'){ ?>
<?php $form = ActiveForm::begin([ 'method' => 'POST','id' => 'addproject-form', 'options' => ['enctype' => 'multipart/form-data']]) ?>
<?= $form->field($form_model, 'name') ?>
<?= $form->field($form_model, 'url') ?>
<?= $form->field($form_model, 'resurs') ?>
<?= $form->field($form_model, 'studio') ?>
<?= $form->field($form_model, 'pic')->fileInput() ?>
<?= Html::submitButton('Добавить', ['class' => 'btn btn-success']) ?>
<?php ActiveForm::end() ?>
<? }
?>
</div>

Controller

public function actionAddproject()
    {
    $this->enableCsrfValidation = false;
    
    $form_model = new ProjectAddForm();
        if($form_model->load(\Yii::$app->request->post())){
          
          $name_form = $_POST['ProjectAddForm']['name'];
          $url_form = $_POST['ProjectAddForm']['url'];
          $resurs_form = $_POST['ProjectAddForm']['resurs'];
          $studio = $_POST['ProjectAddForm']['studio'];
          $pic = $_FILES['ProjectAddForm']['name']['pic'];
          
            $form_model -> pic = UploadedFile::getInstance($form_model,'pic');		
                 $form_model -> pic -> saveAs('projects/' .$pic);

            $date = new Projects();

      
             $date ->name = $name_form;
             $date ->url = $url_form;
             $date ->resurs = $resurs_form;
             $date ->studio = $studio;
             $date ->pic = $pic;
             $date->save();			
        }	
        return $this->render('addproject', compact('form_model'));	
    }

The data is successfully saved to the database, but the file itself is not saved to the correct folder.