Fatal error: Uncaught Error: Class "Symfony\Component\Mime\Part\AbstractMultipartPart" not found in E:\xampp\htdocs\stms\vendor\symfony\mime\Part\Multipart\RelatedPart.php:20 Stack trace: #0 {main} thrown in E:\xampp\htdocs\stms\vendor\symfony\mime\Part\Multipart\RelatedPart.php on line 20