This means that you likely do not have the appropriate license for the images/content on the landing page.
How To Fix This
Two options:
Amend the landing page to conform to policy and resubmit the ads. You can find out how to resubmit your campaign here.
Submit to Realize the appropriate documentation demonstrating you have the rights to the images or content used
Some common explanations why campaign ads get rejected for this reason include:
Using other brands logos in a promotional context without their permission
Using government symbols and buildings in a promotional context without permission
Using a celebrity’s photo in a promotional context without permission
Using a photo from an online gallery that is copyrighted without permission
Using plagiarized material from a news article or other copyrighted content
To learn more about this rejection reason, click here.
To learn how to fix and resubmit your campaign or campaign ad, click here.