ERR_CONNECTION_TIMED_OUT on login, and errors to upgrade

Your software
My Mautic version is: cant check
My PHP version is: 7.4.6
My Database type and version is: MariaDB

Your problem
My problem is:
When connecting to Mautic, I get a ERR_CONNECTION_TIMED_OUT on login page and wont appears anything.

Tried to update using command , but got error
php bin/console mautic:update:apply
PHP Warning: Uncaught ReflectionException: Class “Swift_Mime_Message” not found while loading “MauticPlugin\AFMailgunBundle\Swiftmailer\Transport\MailgunTransport”. in /var/www/html/janeri/mautic/vendor/symfony/config/Resource/ClassExistenceResource.php:181
Stack trace:
#0 [internal function]: Symfony\Component\Config\Resource\ClassExistenceResource::throwOnRequiredClass()
#1 /var/www/html/janeri/mautic/plugins/AFMailgunBundle/Swiftmailer/Transport/MailgunTransport.php(22): spl_autoload_call()
#2 /var/www/html/janeri/mautic/vendor/composer/ClassLoader.php(571): include(’/var/www/html/j…’)
#3 /var/www/html/janeri/mautic/vendor/composer/ClassLoader.php(428): Composer\Autoload\includeFile()
#4 [internal function]: Composer\Autoload\ClassLoader->loadClass()
#5 [internal function]: spl_autoload_call()
#6 /var/www/html/janeri/mautic/vendor/symfony/config/Resource/ClassExistenceResource.php(84): class_exists()
#7 /var/www/html/janeri/mautic/vendor/symfony/dependency-injection/ContainerBuilder.php(353): Symfony\Component\Config in /var/www/html/janeri/mautic/vendor/symfony/config/Resource/ClassExistenceResource.php on line 181
PHP Fatal error: Could not check compatibility between MauticPlugin\AFMailgunBundle\Swiftmailer\Transport\MailgunTransport::send(Swift_Mime_Message $message, &$failedRecipients = NULL) and Swift_Transport_AbstractSmtpTransport::send(Swift_Mime_SimpleMessage $message, &$failedRecipients = NULL), because class Swift_Mime_Message is not available in /var/www/html/janeri/mautic/plugins/AFMailgunBundle/Swiftmailer/Transport/MailgunTransport.php on line 61

These errors are showing in the log:
No error on /var/logs/

Steps I have tried to fix the problem:
Removed from Cloudflare (direct to server now)
Fixed permissions, and tried to update

Anyone can help me with these errors? Thanks!