在应用购买交易失败。 SKPayment不工作？

Question

我遵循了本教程http://www.techotopia.com/index.php/An_iOS_7_In-App_Purchase_Tutorial

- (IBAction)btnBuy:(id)sender {
    NSLog(@"product name: %@", self.product.price);
    SKMutablePayment *payment = [SKMutablePayment paymentWithProduct:self.product];
    payment.quantity = 1;
    [[SKPaymentQueue defaultQueue] addPayment:payment];
}


-(void) getProductInfo: (FirstViewController *) viewController {
    NSLog(@"Enter get Product Info method");
    self.fvController = viewController;
    //getting the product information
    if ([SKPaymentQueue canMakePayments]) {
        SKProductsRequest *request =[[SKProductsRequest alloc] initWithProductIdentifiers:[NSSet setWithObject:self.productID]];
        request.delegate = self;
        [request start];
    } else {
        NSLog(@"Product request failed");
        self.tvProductDes.text = @"Please enable In App Purchase in Settings";
    }

}

#pragma mark -
#pragma mark SKProductsRequestDelegate

-(void) productsRequest:(SKProductsRequest *)request didReceiveResponse:(SKProductsResponse *)response {
    NSLog(@"Enter Products Request method");
    NSArray *products = response.products;

    if (products.count != 0)
    {
        self.product = products[0];
        NSLog(@"%@", self.product.localizedTitle);
        btnBuy.enabled = YES;
        //_productTitle.text = _product.localizedTitle;
        tvProductDes.text = product.localizedDescription;

    } else {
        NSLog(@"Product not found");
    }

    products = response.invalidProductIdentifiers;

    for (SKProduct *p in products)
    {
        NSLog(@"Product not found: %@", p);
    }


}

观察者设置在另一个视图控制器中：

self.purchaseController = [self.storyboard instantiateViewControllerWithIdentifier:@"purchaseVC"];
    [[SKPaymentQueue defaultQueue] addTransactionObserver: self.purchaseController];

在上面的代码中，请求产品正常工作。但是，在调用btnBuy Action时，应用程序中不会返回任何响应。

有谁知道什么是错的？我认为这是SKMutablePayment。

我的产品已在iTunes上，并已准备好提交状态。任何帮助将不胜感激。