protected function getPayloadInstance(): AppInterface {
        if (!($this->instance instanceof AppInterface)) {
            $appName = $this->get('appname', null);
            $appNamespace = $this->get('appnamespace', null);

            // Run App
            $appClassName = ucfirst($appName);
            if (!is_null($appNamespace)) {
                $appClassName = "\\{$appNamespace}\\{$appClassName}";
            }

            $this->instance = $this->di->get($appClassName);
        }
        return $this->instance;
    }