GADInterstitial only presenting first time and delegate methods not being called - ios

Question

I am using Admob for interstitials in my iOS app. I have a test ad set up and it works correctly only the first time I go through the app flow. Subsequent attempts do not show the test ad or call the delegate methods. Below is the GADInterstitial ad setup in my UIViewController
ViewController.h
#interface ViewController : UIViewController <GADInterstitialDelegate>
#property(nonatomic, strong) GADInterstitial *interstitial;
ViewController.m
-(void)viewDidLoad{
self.interstitial = [[GADInterstitial alloc] initWithAdUnitID:#"ca-app-pub-//adID"];
self.interstitial.delegate = self;
GADRequest *request = [GADRequest request];
// Requests test ads on test devices.
request.testDevices = #[#"//test device ID"];
[self.interstitial loadRequest:request];
}
I call the ad from an IBAction. If the user has paid for the app or has used the IBAction under a number of times, then the ad does not show. If user has not paid or used the IBAction over a certain number of times, the ad shows. NSUserDefaults does the check, and if user does IBAction under a certain # of times, fires another method, and increments NSUserDefaults to keep track of how many times user has performed action. I tried using other ad networks, and this same NSUserDefault check worked fine.
In the ViewController.m viewDidLoad.
-(void)action{
if (([[NSUserDefaults standardUserDefaults] integerForKey:#"AdShow"] < 2) || ([[NSUserDefaults standardUserDefaults] integerForKey:#"DidBuyInAppPurchase"] == 1)) {
[self doOtherAction];
NSInteger integer = [[NSUserDefaults standardUserDefaults]integerForKey:#"AdShow"];
NSInteger newInteger = integer + 1;
[[NSUserDefaults standardUserDefaults] setInteger:newInteger forKey:#"AdShow"];
}
else{
NSInteger newInteger = 0;
[[NSUserDefaults standardUserDefaults] setInteger:newInteger forKey:#"AdShow"];
if ([self.interstitial isReady]) {
[self.interstitial presentFromRootViewController:self];
}
}
}];
}
The delegate methods are below also in viewDidLoad
- (void)interstitialWillPresentScreen:(GADInterstitial *)ad {
}
- (void)interstitialWillDismissScreen:(GADInterstitial *)ad {
NSLog(#"interstitialWillDismissScreen");
}
- (void)interstitialDidDismissScreen:(GADInterstitial *)ad {
[self doOtherAction];
}
- (void)interstitial:(GADInterstitial *)ad
didFailToReceiveAdWithError:(GADRequestError *)error {
[self doOtherAction];
NSLog(#"interstitial:didFailToReceiveAdWithError: %#", [error localizedDescription]);
}

Answer 1

The GADInterstitial should go in viewWillAppear not viewDidLoad. For some reason putting it in viewDidLoad causes it not to load with the ad.