Same issue. It appears its an issue with how SS ID's product. We assign a SKU. FB looks for the SKU, but SS has a long number that FB thinks is the SKU. What is weird about this, it sometimes worked, sometimes didn't. FB help was useless when I tried to fix it 9 months ago. Now never works. still a problem. SS needs to direct FB to read the SKU, or need some kind of CSS that redefines Content ID.