邮件提醒无法使用，急等

[jiangtao-lee]

.env:
MAIL_DRIVER=smtp
MAIL_HOST=smtp.126.com
MAIL_PORT=25
MAIL_ENCRYPTION=null
MAIL_USERNAME=xxxxxx@126.com
MAIL_PASSWORD=授权码
MAIL_FROM_NAME=xxxxx
MAIL_FROM_ADDRESS=xxxxx@126.com

报错信息：
[2018-05-26 10:21:21] production.ERROR: Expected response code 220 but got code "502", with message "502 5.5.2 Error: command not recognized
" {"exception":"[object] (Swift_TransportException(code: 502): Expected response code 220 but got code "502", with message "502 5.5.2 Error: command not recognized
" at /data/www/riseon-operation/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php:419)
[stacktrace]
#0 /data/www/riseon-operation/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(317): Swift_Transport_AbstractSmtpTransport->assertResponseCode('502 5.5.2 Error...', Array)
\1 /data/www/riseon-operation/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/EsmtpTransport.php(272): Swift_Transport_AbstractSmtpTransport->executeCommand('STARTTLS
', Array, Array)
\2 /data/www/riseon-operation/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/EsmtpTransport.php(313): Swift_Transport_EsmtpTransport->executeCommand('STARTTLS
', Array)
#3 /data/www/riseon-operation/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/AbstractSmtpTransport.php(131): Swift_Transport_EsmtpTransport->doHeloCommand()
#4 /data/www/riseon-operation/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Mailer.php(67): Swift_Transport_AbstractSmtpTransport->start()
#5 /data/www/riseon-operation/vendor/laravel/framework/src/Illuminate/Mail/Mailer.php(451): Swift_Mailer->send(Object(Swift_Message), Array)
#6 /data/www/riseon-operation/vendor/laravel/framework/src/Illuminate/Mail/Mailer.php(235): Illuminate\Mail\Mailer->sendSwiftMessage(Object(Swift_Message))
#7 /data/www/riseon-operation/vendor/laravel/framework/src/Illuminate/Notifications/Channels/MailChannel.php(64): Illuminate\Mail\Mailer->send('notifications.e...', Array, Object(Closure))
#8 /data/www/riseon-operation/vendor/laravel/framework/src/Illuminate/Notifications/NotificationSender.php(113): Illuminate\Notifications\Channels\MailChannel->send(Object(Piplin\Models\Hook), Object(Piplin\Bus\Notifications\Task\TaskSucceededNotification))
#9 /data/www/riseon-operation/vendor/laravel/framework/src/Illuminate/Notifications/NotificationSender.php(89): Illuminate\Notifications\NotificationSender->sendToNotifiable(Object(Piplin\Models\Hook), 'b604434b-e158-4...', Object(Piplin\Bus\Notifications\Task\TaskSucceededNotification), 'mail')
#10 /data/www/riseon-operation/vendor/laravel/framework/src/Illuminate/Notifications/ChannelManager.php(50): Illuminate\Notifications\NotificationSender->sendNow(Object(Illuminate\Database\Eloquent\Collection), Object(Piplin\Bus\Notifications\Task\TaskSucceededNotification), Array)
#11 /data/www/riseon-operation/vendor/laravel/framework/src/Illuminate/Notifications/SendQueuedNotifications.php(57): Illuminate\Notifications\ChannelManager->sendNow(Object(Piplin\Models\Hook), Object(Piplin\Bus\Notifications\Task\TaskSucceededNotification), Array)
#12 [internal function]: Illuminate\Notifications\SendQueuedNotifications->handle(Object(Illuminate\Notifications\ChannelManager))
#13 /data/www/riseon-operation/vendor/laravel/framework/src/Illuminate/Container/BoundMethod.php(29): call_user_func_array(Array, Array)