Posting this in case it helps someone else. I couldn’t get all of my items to sync from WooCommerce to Zettle POS. Some did and some did not. After reading through a whole lot of Zettle info, I found that if you are using variations, the SKU for each variation can only hold so many character spaces or it won’t sink. Once I went in the products that weren’t synced and shortened SKUs and updated, they immediately synced. Hope this helps.