Fatal error: Uncaught Error: Class "Illuminate\Support\ServiceProvider" not found in /home/sourceex/public_html/pm/vendor/laravel/slack-notification-channel/src/SlackChannelServiceProvider.php:9 Stack trace: #0 {main} thrown in /home/sourceex/public_html/pm/vendor/laravel/slack-notification-channel/src/SlackChannelServiceProvider.php on line 9