Fatal error: Uncaught Symfony\Component\Yaml\Exception\ParseException: File "/var/www/html/app/config/parameters.yml" cannot be read. in /var/www/html/vendor/symfony/symfony/src/Symfony/Component/Yaml/Parser.php:72 Stack trace: #0 /var/www/html/vendor/symfony/symfony/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php(661): Symfony\Component\Yaml\Parser->parseFile('/var/www/html/a...', 768) #1 /var/www/html/vendor/symfony/symfony/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php(117): Symfony\Component\DependencyInjection\Loader\YamlFileLoader->loadFile('/var/www/html/a...') #2 /var/www/html/vendor/symfony/symfony/src/Symfony/Component/Config/Loader/FileLoader.php(153): Symfony\Component\DependencyInjection\Loader\YamlFileLoader->load('/var/www/html/a...', NULL) #3 /var/www/html/vendor/symfony/symfony/src/Symfony/Component/Config/Loader/FileLoader.php(90): Symfony\Component\Config\Loader\FileLoader->doImport('/var/www/html/a...', NULL, false, '/var/www/html/a...') #4 /var/www/html/vendor/ in /var/www/html/vendor/symfony/symfony/src/Symfony/Component/Config/Loader/FileLoader.php on line 168