how change date format in Carbon/laravel?

I need help please to change date format to be like this May-21 22:22:22

This is for Laravel 5 with carbon

private function validateDate($date)
{
    $d = \DateTime::createFromFormat('Y-m-d\TH:i:s\Z', $date);
    return $d && $d->format('Y-m-d\TH:i:s\Z') == $date;
}


private function formatDateForParis($date){             
        if ($this->validateDate($date)) 
        {       

          $datetime = new \DateTime($date);
      $timezone = date_default_timezone_get();
      $tZone = new \DateTimeZone($timezone);

      $datetime->setTimezone($tZone);
          return $datetime->format('Y-m-d H:i:s');
                        
        }else{          
                return Carbon::createFromFormat('Y-m-d H:i:s', $date)->setTimezone('Europe/paris')->format('Y-m-d H:i:s');
        }

}

when i'm try to change it i get this error :

Unexpected data found. Trailing data

via Chebli Mohamed