Fatal error: Uncaught Symfony\Component\DependencyInjection\Exception\RuntimeException: A string value must be composed of strings and/or numbers, but found parameter "mailer_user" of type "null" inside string value "smtp://%mailer_user%:%mailer_password%@%mailer_host%:%mailer_port%". in /var/www/clients/client322/web1037/web/vendor/symfony/dependency-injection/ParameterBag/ParameterBag.php:248 Stack trace: #0 [internal function]: Symfony\Component\DependencyInjection\ParameterBag\ParameterBag->Symfony\Component\DependencyInjection\ParameterBag\{closure}() #1 /var/www/clients/client322/web1037/web/vendor/symfony/dependency-injection/ParameterBag/ParameterBag.php(234): preg_replace_callback() #2 /var/www/clients/client322/web1037/web/vendor/symfony/dependency-injection/ParameterBag/ParameterBag.php(205): Symfony\Component\DependencyInjection\ParameterBag\ParameterBag->resolveString() #3 /var/www/clients/client322/web1037/web/vendor/symfony/dependency-injection/ParameterBag/ParameterBag.php(158): Symfony\Component\DependencyInjection\ParameterBag\ParameterBag->resolveValue() #4 /var/www/clients/client322/web1037/web/vendor/symfony/dependency-injection/ParameterBag/EnvPlaceholderParameterBag.php(150): Symfony\Component\DependencyInjection\ParameterBag\ParameterBag->resolve() #5 /var/www/clients/client322/web1037/web/vendor/symfony/dependency-injection/Compiler/ResolveParameterPlaceHoldersPass.php(58): Symfony\Component\DependencyInjection\ParameterBag\EnvPlaceholderParameterBag->resolve() #6 /var/www/clients/client322/web1037/web/vendor/symfony/dependency-injection/Compiler/Compiler.php(80): Symfony\Component\DependencyInjection\Compiler\ResolveParameterPlaceHoldersPass->process() #7 /var/www/clients/client322/web1037/web/vendor/symfony/dependency-injection/ContainerBuilder.php(767): Symfony\Component\DependencyInjection\Compiler\Compiler->compile() #8 /var/www/clients/client322/web1037/web/vendor/symfony/http-kernel/Kernel.php(506): Symfony\Component\DependencyInjection\ContainerBuilder->compile() #9 /var/www/clients/client322/web1037/web/vendor/symfony/http-kernel/Kernel.php(759): Symfony\Component\HttpKernel\Kernel->initializeContainer() #10 /var/www/clients/client322/web1037/web/vendor/symfony/http-kernel/Kernel.php(185): Symfony\Component\HttpKernel\Kernel->preBoot() #11 /var/www/clients/client322/web1037/web/src/AppKernel.php(36): Symfony\Component\HttpKernel\Kernel->handle() #12 /var/www/clients/client322/web1037/web/web/app.php(23): AppKernel->handle() #13 {main} thrown in /var/www/clients/client322/web1037/web/vendor/symfony/dependency-injection/ParameterBag/ParameterBag.php on line 248