操作返回了无效的状态码“未经授权”

Question

我正在尝试使用从天蓝色门户复制的密钥访问天蓝色资源（QNA）：

           // <Authorization>
              var subscriptionKey = Environment.GetEnvironmentVariable("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx");
        var client = new QnAMakerClient(new ApiKeyServiceClientCredentials(subscriptionKey)) { Endpoint = "https://westus.api.cognitive.microsoft.com/" };
        // </Authorization>

        // <EndpointKey>
        var endpointhostName = Environment.GetEnvironmentVariable("iakpmgpoc.azurewebsites.net");
        var endpointKey = Environment.GetEnvironmentVariable("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx");

仍然出现“未经授权的访问”问题