Fatal error: Uncaught Error: Interface "Magento\Framework\EntityManager\Operation\ExtensionInterface" not found in /var/www/magento/html/app/code/Amasty/Rules/Model/SalesRule/SaveHandler.php:19 Stack trace: #0 {main} thrown in /var/www/magento/html/app/code/Amasty/Rules/Model/SalesRule/SaveHandler.php on line 19