无法与PayPal服务器通信

Question

我在面对iOS的PayPal SDK集成时遇到了一些问题。我创建了基于美国的沙盒帐户。在示例应用程序代码中使用了以下CLIENT_ID。

PayPalEnvironmentSandbox：@"AFcWxV21C7fd0v3bYYYRCpSSRl31AqobHyAcg9npaCbtFnE7xlWC0JwE"

当我在设备上运行此项目时，它会出错。

这是控制台日志：

PayPal iOS SDK Version: PayPal iOS SDK 2.12.7 
Environment: Optional("mock"). Accept credit cards? Optional(false) 
Environment: Optional("sandbox"). Accept credit cards? Optional(false) PayPal Payment Cancelled

我在iPhone6上运行示例应用程序项目（8.1） 这个问题是： 如果我尝试使用不同的网络，它会给出以下错误日志：

PayPal iOS SDK Version: PayPal iOS SDK 2.12.7
2015-11-19 13:09:20.512 PayPal-iOS-SDK-Sample-App[1553:56432] CFNetwork SSLHandshake failed (-9806)
2015-11-19 13:09:20.526 PayPal-iOS-SDK-Sample-App[1553:56432] CFNetwork SSLHandshake failed (-9806)
2015-11-19 13:09:20.593 PayPal-iOS-SDK-Sample-App[1553:56432] CFNetwork SSLHandshake failed (-9806)
2015-11-19 13:09:20.600 PayPal-iOS-SDK-Sample-App[1553:56432] CFNetwork SSLHandshake failed (-9806)
2015-11-19 13:09:20.661 PayPal-iOS-SDK-Sample-App[1553:56432] CFNetwork SSLHandshake failed (-9806)
2015-11-19 13:09:20.662 PayPal-iOS-SDK-Sample-App[1553:56432] NSURLConnection/CFURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9806)
2015-11-19 13:09:20.664 PayPal-iOS-SDK-Sample-App[1553:56432] CFNetwork SSLHandshake failed (-9806)
2015-11-19 13:09:20.666 PayPal-iOS-SDK-Sample-App[1553:56432] NSURLConnection/CFURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9806)
2015-11-19 13:09:22.461 PayPal-iOS-SDK-Sample-App[1553:56432] CFNetwork SSLHandshake failed (-9806)
2015-11-19 13:09:22.520 PayPal-iOS-SDK-Sample-App[1553:56432] CFNetwork SSLHandshake failed (-9806)
2015-11-19 13:09:22.578 PayPal-iOS-SDK-Sample-App[1553:56432] CFNetwork SSLHandshake failed (-9806)
2015-11-19 13:09:22.580 PayPal-iOS-SDK-Sample-App[1553:56432] NSURLConnection/CFURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9806)