[iOS SwiftUI] Unable to show paywall

I have follow your guide to this page https://www.revenuecat.com/docs/tools/paywalls/displaying-paywalls

And implement the code in my view, but the paywall is not showing up, what am I missing?

```

            .presentPaywallIfNeeded(

                requiredEntitlementIdentifier: "pro",

                purchaseCompleted: { customerInfo in

                    print("Purchase completed: \(customerInfo.entitlements)")

                },

                restoreCompleted: { customerInfo in

                    // Paywall will be dismissed automatically if "pro" is now active.

                    print("Purchases restored: \(customerInfo.entitlements)")

                }

            )

```