Having an issue with my site showing duplicate Facebook Pixel IDs. I've tried unlinking the pixel from Ads in settings, and there isn't another script manually added in the Page headers. Using Pixel Helper Chrome plugin, it says there is just one pixel active on the site.
I've seen some work arounds within the script, but that's not how the Pixel is being pulled into our site in the first place.
It is difficult to say without looking into your setup. If you use Google Tag Manager, make sure you are not using the pixel there. I hope the issue has been resolved by now.