This error means that the link that the advertiser requested in the original briefing isn’t found in the published article. Please check the link that was requested (in the Briefing section or in the Content section in case the advertiser had provided the content himself) and make sure the link in your article is exactly the same.
If you believe the link you have added is the one requested in the briefing, or have agreed to a change of link with the advertiser in the messaging tool, please contact our support team.