Fatal error: Uncaught Error: Call to a member function checkProduct() on null in /var/www/opencart/catalog/controller/product/product.php:870 Stack trace: #0 /var/www/opencart/system/storage/modification/system/engine/action.php(79): ControllerProductProduct->index() #1 /var/www/opencart/catalog/controller/startup/router.php(25): Action->execute() #2 /var/www/opencart/system/storage/modification/system/engine/action.php(79): ControllerStartupRouter->index() #3 /var/www/opencart/system/engine/router.php(93): Action->execute() #4 /var/www/opencart/system/engine/router.php(65): Router->execute() #5 /var/www/opencart/system/framework.php(174): Router->dispatch() #6 /var/www/opencart/system/startup.php(104): require_once('/var/www/openca...') #7 /var/www/opencart/index.php(35): start() #8 {main} thrown in /var/www/opencart/catalog/controller/product/product.php on line 870