The URL for the ATOM feed for all of your store's products can be found at http://yourdomain.com/collections/all.atom
You can also get the ATOM feed for specific collections by using http://yourdomain.com/collections/collection-handle.atom instead.
You can try and app for it. " Facebook Product Feed (by Flexify) " you'll find it in the app store and its free. I found facebook business manager too complicated and went back to the old version of it and just used a retargeting add every few weeks to pull customers back, which seams to work fine. You need a lot of traffic for dynamic ads to work and facebook don't make it easy to set up.
Ok, It seems like I found the solution and the same costed me 5 hours from this morniing hah.
Tried the "Facebook Product Feed" suggested above and when created Product Feed inside business manager, it said 160+ product lol, when I have only 16. I guess it calculated the variants too.
Later I was searching for app that integrates the Facebook Pixel correctly and either I was getting "Page View" on the Customer Info, Shipping Method and Payment method or Pixel cant match products errors - which is totally unimportant by my opinion - I found this Pixel Perfect app that does both with ease!!!
Here you go, problem solved with Pixel and Product Feeds.
For anyone that wants to know how to create your own custom Facebook product feed, here is a brief writeup on how to do so using a custom collection template:
I hope you have got the best solution for the issue you were facing. I am leaving my answer so others who are facing the same issue can get little help :) Trackify facebook pixel app takes care almost all such issues related to facebook marketing and help you get maximum ROI