Ads won’t load for game rewards

The app developer may not have updated their software to ensure compatibility with the iOS version your device is currently running.

If you encounter any challenges with third-party applications, the best course of action is to directly contact the app developer for further assistance. Here's a brief guide on how to do it:

1. Identify the app developer.
2. Visit their website or app store listing.
3. Look for their contact information or support channels.
4. Clearly describe the issue you are facing.
5. Provide any necessary information they may need.
6. Follow their instructions and provide feedback.
7. Be patient and follow up if needed.

By reaching out to the app developer, you increase your chances of receiving accurate and personalized support for the challenges you're experiencing. To contact an App developer --> How to contact an app developer - Apple Support

There are really only about 5 ad networks that all games use to display ads. If you have internet connectivity and able to load web pages in Safari, it is likely that ad network has gone done and will return shortly. They may be performing maintenance on their servers or a glitch that will be resolved. The ad network usually display its name in one of the corners of the ad when it is displayed. You can also contact the developer of the apps to make them aware of the issue.

Exactly the same issue here.