Fatal error: Uncaught Error: Class 'Symfony\Component\Mime\Header\UnstructuredHeader' not found in /home/benjamincb/demos/acdg-site/vendor/symfony/mailer/Header/TagHeader.php:19 Stack trace: #0 {main} thrown in /home/benjamincb/demos/acdg-site/vendor/symfony/mailer/Header/TagHeader.php on line 19