Method RequestInterstitialAd
RequestInterstitialAd()
Starts loading the interstitial ad. Returns immediately; the ad loads asynchronously and raises OnInterstitialAdLoaded when ready. On load failure it retries with a delayed exponential backoff (Google discourages immediate in-callback retries). Call once after InitializeAsync(AdMobModuleConfig) completes; reloads automatically after each show.
public static void RequestInterstitialAd()