We found a great article to introduce how Apple IOS 14 will limit your Facebook ads performance.
This update will limit the Facebook Pixel tracking system and you will see a decrease in conversion reports.
For the details please click: https://bit.ly/3rox32t
How to deal with these? Facebook provides a good update guidebook.
If your ads are optimized for app
You need to update Facebook's SDK for iOS 14 version 8.1
If your ads are optimized for conversion and event, you may need to You may need to verify your website's domain and Configure eight preferred web conversion events per domain in Events Manager.