Fatal error: Uncaught Error: Class "WP_Async_Request" not found in /home/workings/public_html/hidden/wp-content/plugins/ninja-forms/includes/Libraries/BackgroundProcessing/classes/wp-background-process.php:16 Stack trace: #0 {main} thrown in /home/workings/public_html/hidden/wp-content/plugins/ninja-forms/includes/Libraries/BackgroundProcessing/classes/wp-background-process.php on line 16