Sync Shopify inventory with Google sheets

I just want to update the product quantity in my google sheet whever someone places an order, but the problem is it's not working properly when the customer has multiple items in their cart, and shopify does not return a json object in the API call as well, so I'm not able to use a function as well.

Please help me with this issue

Thanks

You may want to turn off simple response. Can you give Screenshots of what data is shopify is returning for products