Testing modally presented view controller presenting another view controller

I am trying to test this controller that is presented. I want to test if I click a button in this controller that the correct controller is presented.

I ran in simulator and it is presenting but when I try to test this using expect(sut.presentedViewController).to(beAKindOf(UIAlertController.self) it throws an error saying it is nil.

The method I call before this expect simply calls the method sut.presentAlert()