Braintree Paypal validation error: SFSafariViewController does not switch back to application

Question

I am using Xcode 8, swift 3. installed through carthage and version of Braintree 4.7.2.

by clicking the continue button using the buy sandbox button, it will not return to the application and will not receive a failure and will not receive errors.

There is something that I missed during installation.

I use PayPal when checking time.

@IBAction func customPayPalButtonPressed(_ sender: AnyObject) { let payPalDriver : BTPayPalDriver = BTPayPalDriver.init(apiClient: self.apiClient!) payPalDriver.viewControllerPresentingDelegate = self payPalDriver.appSwitchDelegate = self let payPalRequest = BTPayPalRequest(amount: "100.00") payPalRequest.currencyCode = "USD" payPalDriver.requestOneTimePayment(payPalRequest) { (tokenizedPayPalAccount, error) -> Void in if (tokenizedPayPalAccount != nil) { print(tokenizedPayPalAccount.debugDescription) }else if (error != nil) { print(error?.localizedDescription) print(error.debugDescription) }else { print("Cancled") } } }