Add Support for Magento 2 Inventory Reservations
Magento 2 changed the way inventory management is handled. It no longer relies on the quantity field, but rather a combination of the quantity field and inventory reservations to obtain a "salable quantity". See: https://devdocs.magento.com/guides/v2.4/inventory/reservations.html
The inventory reservations in Magento are deducted from the quantity when the order is marked as complete (typically when shipped).
The problem is evident when Connex is syncing both orders and inventory to Quickbooks. Once Connex syncs an order to Quickbooks, Quickbooks immediately adjusts inventory accordingly. Connex then syncs that inventory value to Magento's quantity value.
This is incompatible with Magento 2 because the quantity in Magento is not representative of the actual saleable inventory.
The temporary solution/workaround is to only sync orders that are complete. This works but may not be ideal for most customers. A better solution would be to take into account Magento's inventory reservations system and look at the saleable quantity during synchronization and/or take the relevant inventory reservations out of the system for that order.