Fatal error: Uncaught Error: Class "SLB_API\Controller\REST_Controller" not found in /var/www/html1/wp-content/plugins/salon-booking-system/src/SLB_API/Controller/AvailabilityIntervals_Controller.php:10 Stack trace: #0 {main} thrown in /var/www/html1/wp-content/plugins/salon-booking-system/src/SLB_API/Controller/AvailabilityIntervals_Controller.php on line 10