Facebook shop main product thumbnail

[zoeysgarage]

I've recently set up Facebook and Instagram shops for my Shopify products. On my Shopify site, each product has a main thumbnail that I chose (generally a close-up) and multiple others to show color variations, etc. I want that close-up image to be the main thumbnail in my Facebook and Instagram shops also. But that isn't what's happening. Each product seems to be getting a random main thumbnail. Do I have some control over this?