Fatal error: Uncaught TypeError: Argument 1 passed to JTL\Helpers\Product::showAvailabilityForm() must be an instance of JTL\Catalog\Product\Artikel, null given, called in /usr/www/users/wohnfu/filter.php on line 125 and defined in /usr/www/users/wohnfu/includes/src/Helpers/Product.php:857 Stack trace: #0 /usr/www/users/wohnfu/filter.php(125): JTL\Helpers\Product::showAvailabilityForm(NULL, 'Y') #1 [internal function]: {closure}(NULL, 12) #2 /usr/www/users/wohnfu/includes/vendor/illuminate/collections/Collection.php(640): array_map(Object(Closure), Array, Array) #3 /usr/www/users/wohnfu/includes/vendor/illuminate/collections/Collection.php(1302): Illuminate\Support\Collection->map(Object(Closure)) #4 /usr/www/users/wohnfu/filter.php(129): Illuminate\Support\Collection->transform(Object(Closure)) #5 /usr/www/users/wohnfu/index.php(13): require('/usr/www/users/...') #6 {main} thrown in /usr/www/users/wohnfu/includes/src/Helpers/Product.php on line 857