A scenario where I have seen this problem occurring is when you have more than 1 catalog connected to the same shop.
I have only 1 Catalogue.
Also, please confirm your Facebook for WooCommerce version.
Version 2.6.9
On the second issue illustrated in the screenshot below, it looks like that is a parent product, and its variant.
No, we don’t have any product with variant
Are you facing any issues with orders on the products in the screenshot above?
No, it’s our top seller product, but we may face some problems if we run retargeting campaign using DPA
Thanks a lot fo your answer!