Not receiving PurchasesDelegate callback when user cancels free trial plan

By using the following code, I can receive PurchasesDelegate callback, when user subscribes to a free trial plan.

However, I am not able to receive PurchasesDelegate callback, when user cancels the free trial plan.

class AppDelegate: UIResponder, UIApplicationDelegate {

    // https://www.revenuecat.com/docs/integrations/attribution/apple-search-ads
    // https://www.revenuecat.com/docs/integrations/attribution/facebook-ads#3-send-revenuecat-events-into-facebook-ads-manager
    private func initRevenueCat() {
        Purchases.configure(with:
            .init(withAPIKey: "appl_???")
            .with(
                purchasesAreCompletedBy: .myApp,
                storeKitVersion: .storeKit2
            )
        )

        Purchases.shared.attribution.enableAdServicesAttributionTokenCollection()

        // Automatically collect the $idfa, $idfv, and $ip values
        Purchases.shared.attribution.collectDeviceIdentifiers()
        // REQUIRED: Set the Facebook anonymous Id
        Purchases.shared.attribution.setFBAnonymousID(FBSDKCoreKit.AppEvents.shared.anonymousID)

        Purchases.shared.delegate = self
    }
}

extension AppDelegate: PurchasesDelegate {
    func purchases(_ purchases: Purchases, receivedUpdated customerInfo: CustomerInfo) {
        // handle any changes to customerInfo
    }
}

May I know how I can fix this? Thanks.