Fatal error: Uncaught Error: Class 'Gelf\Transport\AbstractTransport' not found in /var/www/html/ng-crm/yiiapp/vendor/graylog2/gelf-php/src/Gelf/Transport/HttpTransport.php:28 Stack trace: #0 {main} thrown in /var/www/html/ng-crm/yiiapp/vendor/graylog2/gelf-php/src/Gelf/Transport/HttpTransport.php on line 28