NotificationCenter observer method not being executed in some cases

I'm working with a deeplink I have to implement to my app. The deeplink is working because in some cases i will explain later the method is being executed. So when I tap the deeplink with a deeplink-tester-web I detect if the url is which I want and, if it's the case, i post a notification to NotificationCenter with a string parameter I need.

Case 1. I tap the deeplink when the view controller with the addObserver method is at the background with the app itself. It works (the only case)

Case 2. The app is closed so the deeplink opens the app directly in that view controller (the method is no being called event if the notification is there) Why?

Case 3. The app is at the background but in another screen. When I tap the deeplink and, after returning to the app, travel to my viewController the method is not called when the ViewController becomes visible. Why?

I've not seen anything in the documentation that can help me and i cannot access to the array of observers because the API does not allow that

Thanks. Any help will be appreciate.

Code:

When the deeplink is tapped the app delegate method that manages universal links call to this code when the url is a specific one

@objc func handleRecommendedOffer(offerId: String) {
        NotificationCenter.default.post(name: .deeplinkRecommendedOfferNotification, object: nil, userInfo: ["offerId": offerId])
    }

In my viewcontroller viewDidLoad (i've tried also viewWillAppear too):

NotificationCenter.default.addObserver(self, selector: #selector(goToDetail(notification:)), name: .deeplinkRecommendedOfferNotification, object: nil)

@objc private func goToDetail(notification: Notification) {
        if let userInfo = notification.userInfo, let offerId = userInfo["offerId"] as? String {
            showLoading()
            getOfferViewModel.getOfferDetail(id: offerId)
        }
    }