Fatal error: Uncaught TypeError: Article::related(): Argument #2 ($categoryId) must be of type int, null given, called in /var/www/html/src/controllers/ArticleController.php on line 10 and defined in /var/www/html/src/models/Article.php:145 Stack trace: #0 /var/www/html/src/controllers/ArticleController.php(10): Article::related(51, NULL, 4) #1 /var/www/html/public/index.php(32): ArticleController::show('test-artikel-pl...') #2 /var/www/html/src/Router.php(32): {closure}(Array) #3 /var/www/html/public/index.php(383): Router->dispatch() #4 {main} thrown in /var/www/html/src/models/Article.php on line 145