When adding in-app banners, you may receive an error notification. This could be due to the following issues:
Invalid ad URL
An ad URL is required for each in-app banner
If ad URL is missing, add a URL
URL structure must be valid, i.e:
Test your URL by entering it in a web browser like Safari, Chrome, Firefox.
Invalid Banner Image
An ad image is required for each in-app banner
If the ad image is missing, add an image to the “Banner Image” section by clicking “browse.”