Error loading saving data

Hello everyone

I'm newbee to coding and I recently discovered Grocery Crud and would like to start a small project.

I have install Grocery Crud Ver 2.01 and Codelgniter Ver 4.1.1 in local with Wampserver

I want to capitalize the field Â« nom_ta_clientâ€ in my database but I always have the error â€œLoading saving dataâ€ and if I remove the 2 lines with Callback all is good no mistake.

Could someone tell me where I made a mistake

Thank you for your help and sorry for my poor English

{
public function prepare($post_array)
{
$post_array['nom_ta_client'] = strtoupper(trim($post_array['nom_ta_client']));
return $post_array;
}

function get_init_date($post_array)
{
$post_array['date_creation_ta_client'] = date('d-m-Y');
$post_array['date_maj_ta_client'] = date('d-m-Y H:i:s');
return $post_array;
}

function Client() {
        $crud = new GroceryCrud();

        $crud->setTheme('datatables');

       $crud->setTable('ta_client');

       $crud->columns([
                       'date_creation_ta_client',
                       'date_maj_ta_client',
                       'titre_ta_client',
                       'nom_ta_client',
                       'prenom_ta_client'
                       ]);

        $crud->setSubject('CLIENT');

       $crud->displayAs('date_creation_ta_client','Date de CrÃ©ation');
       $crud->displayAs('date_maj_ta_client','Date de MAJ');
       $crud->displayAs('titre_ta_client','Titre');
       $crud->displayAs('nom_ta_client','Nom');
       $crud->displayAs('prenom_ta_client','PrÃ©nom');

       $crud->requiredFields(['nom_ta_client']);

       $crud->fieldtype('titre_ta_client','enum',array('Mr','Mme','Mlle'));

       $crud->callbackbeforeinsert(array($this,'prepare'));
       $crud->callbackbeforeupdate(array($this,'prepare'));

       $crud->setRead();

       $crud->fieldtype('date_creation_ta_client','invisible');
       $crud->fieldtype('date_maj_ta_client','invisible');

        $output = $crud->render();

        return $this->_TestOutput($output);
    }

    private function _TestOutput($output = null) {
        return view('Test', (array)$output);
    }
}

Phd2000