CardIO can not get my card Info

I am testing the iOS SDK cardIO for credit card scanning, I followed the instructions at https://github.com/card-io/card.io-iOS-SDK , but I open my CardIOPaymentViewController it does not scan my card, there is no callback to " userDidProvideCreditCardInfo: ", otherwise, when the controller is canceled," userDidCancelPaymentViewController: "is called. Did I miss something?

Please note that the card is correctly installed and I am using a visa card.

My source:

@interface TestViewController : UIViewController <CardIOPaymentViewControllerDelegate>

- (IBAction)scanCard:(id)sender;

@end

@implementation TestViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view from its nib.
}

- (IBAction)scanCard:(id)sender{
    CardIOPaymentViewController *scanViewController = [[CardIOPaymentViewController alloc] initWithPaymentDelegate:self];
    scanViewController.appToken = @"app-token";
    scanViewController.collectCVV = YES;
    scanViewController.collectExpiry = YES;
    scanViewController.useCardIOLogo = YES;
    [self.navigationController presentViewController:scanViewController animated:YES completion:nil];
}

- (void)userDidCancelPaymentViewController:(CardIOPaymentViewController *)scanViewController {
    NSLog(@"User canceled payment info");
    // Handle user cancellation here...
    [scanViewController dismissViewControllerAnimated:YES completion:nil];
}

- (void)userDidProvideCreditCardInfo:(CardIOCreditCardInfo *)info inPaymentViewController:(CardIOPaymentViewController *)scanViewController {
    // The full card number is available as info.cardNumber, but don't log that!
    NSLog(@"Received card info. Number: %@, expiry: %02lu/%lu, cvv: %@.", info.redactedCardNumber, (unsigned long)info.expiryMonth, (unsigned long)info.expiryYear, info.cvv);
    // Use the card info...
    [scanViewController dismissViewControllerAnimated:YES completion:nil];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end

Sincerely.