Keep getting this error when pushing WooCommerce orders to QuickBooks Online using MyWorks Sync?
Error
Error:6520: [Missing Inventory Item Quantity, Quantity required for inventory item]
Cause
You have an inventory product selected in MyWorks Sync > Settings > Defaults for Default QBO Coupon Code Product and Default QBO Shipping Product. QuickBooks Online won't accept inventory products for these line items, as they aren't synced over to QuickBooks Online with a quantity in the invoice line item.
Resolution
You should have a generic non-inventory product set for both of these settings. We recommend a product named "Shipping" and a product named "Coupon" or "Discount".