Do you understand how Meta gives credit to ads for conversions in Ads Manager? This is "attribution."
Attribution is often misunderstood. It's not just the direct click that gets the credit. And only one ad will get credit for a single conversion.
Of course, how this is determined has changed during the past year or so.
Read this post for additional details:
https://www.jonloomer.com/facebook-ad-conversion-attribution/
