The HMS Unity Plugin makes it easy to include Huawei Mobile Services into Unity-based games. Authentication, in-app purchases, push alerts, ads, and interaction with gaming services are just a few of the basic capabilities that this formidable tool makes available to your applications.
If all test ads are enabled without setting a splash icon, when loading at runtime, splash ads will get stuck here: https://github.com/EvilMindDevs/hms-unity-plugin/blob/Development/Assets/Huawei/Scripts/Ads/HMSAdsKitManager.cs#L747 And other ads will not work, such as banner, interstitial, and reward ads, because splash ads load first here: https://github.com/EvilMindDevs/hms-unity-plugin/blob/Development/Assets/Huawei/Scripts/Ads/HMSAdsKitManager.cs#L125-L128.
The solution is provided in https://medium.com/huawei-developers-tr/extend-your-advertisement-with-hms-ads-kit-splash-ad-in-unity-3e13f38f3abe. I think adding the splash icon for the demo will make it more convenient for new developers in the future :)