Right pangesture not working correctly

[Ghousepasha-ios]

let left = UIStoryboard(name: "Left", bundle: nil).instantiateInitialViewController()!
        let center = UIStoryboard(name: "Center", bundle: nil).instantiateInitialViewController()!
        let drawer = DrawerMenu(center: center, right: left)
        addChild(drawer)
        view.addSubview(drawer.view)
        drawer.didMove(toParent: self)

above code not working for right swipe pan gesture closing.