Non rewarded Ads

First of all the ads has to be loaded before you can display it. See the code snippet below:

using SA.CrossPlatform.Advertisement;
...

//You can use any configured UM_AdPlatform here
//This example will use Unity ads, that's why we get client with UM_AdPlatform.Unity
UM_iAdsClient client = UM_AdvertisementService.GetClient(UM_AdPlatform.Unity);
client.NonRewardedAds.Load((result) => {
    if (result.IsSucceeded) {
        Debug.Log("NonRewardedAds loaded");
    } else {
        Debug.Log("Failed to load NonRewardedAds: " + result.Error.Message);
    }
});

The load status can always be accessed via IsReady property.

bool ready = client.NonRewardedAds.IsReady;

Once ad content is loaded, you may show it:

m_adsClient.NonRewardedAds.Show(() => {
    Debug.Log("Non Rewarded Ads closed");
});