Anmeldung Absolventenkolloquium

Fatal error: Uncaught Symfony\Component\Form\Exception\InvalidArgumentException: The name "Titel der Abschlussarbeit / Hausarbeit" contains illegal characters. Names should start with a letter, digit or underscore and only contain letters, digits, numbers, underscores ("_"), hyphens ("-") and colons (":"). in /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/FormConfigBuilder.php:635 Stack trace: #0 /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/FormConfigBuilder.php(76): Symfony\Component\Form\FormConfigBuilder::validateName() #1 /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/FormBuilder.php(42): Symfony\Component\Form\FormConfigBuilder->__construct() #2 /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/ResolvedFormType.php(160): Symfony\Component\Form\FormBuilder->__construct() #3 /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/ResolvedFormType.php(81): Symfony\Component\Form\ResolvedFormType->newBuilder() #4 /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/FormFactory.php(52): Symfony\Component\Form\ResolvedFormType->createBuilder() #5 /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/FormBuilder.php(80): Symfony\Component\Form\FormFactory->createNamedBuilder() #6 /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/FormBuilder.php(207): Symfony\Component\Form\FormBuilder->create() #7 /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/FormBuilder.php(160): Symfony\Component\Form\FormBuilder->resolveChildren() #8 /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/FormBuilder.php(166): Symfony\Component\Form\FormBuilder->getForm() #9 /websrv/zs-2001/htdocs/mathematik/mathematik_anmeldung.php(9358): Symfony\Component\Form\FormBuilder->getForm() #10 {main} thrown in /websrv/sw/php/include/symfony/symfony-7.3/vendor/symfony/symfony/src/Symfony/Component/Form/FormConfigBuilder.php on line 635