This is the most common cause of the over reporting problem, so don’t ignore this step.
Open your Facebook Ads Manager top menu and look for “Events Manager”. Click on the link and click on the Pixel ID you have installed on your website.
Click on “Settings” (left side menu) and scroll down until you find an option called “Track Events Automatically Without Code”. Make sure it is turned OFF.

What “Track Events Automatically Without Code” option does?
When this option is turned ON, Facebook’s intelligent algorithm will try to “guess” what your users are doing. It will automatically associate actions to standard events, figuring out when things like add to cart or purchases occur.
The problem is that if your Facebook Pixel already fires those events, you will end up with the same data being reported multiple times.
If you implement your Facebook Pixel with Pixel Conversion Pro that tracks all your pixel events, you must turn OFF “Track Events Automatically Without Code”.
***Important***
Why is Facebook over-reporting purchases?
The most common cause is that you have “Track Events Automatically Without Code” turned ON. Make sure when using Pixel Conversion Pro that this setting is turned OFF for all Pixel ID’s.
Regards,
James (Tech Support)
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Thanks again from all of us here at Pixel Conversion Pro and remember, you are Awesome!