Hello,
The error means Business Central is trying to create/update a Sales Line for document ORD-01026-D5F8H5, but the corresponding Sales Header was never created successfully. From your screenshot, you are using Legacy Sales Order Integration = Enabled, Automatically Create Sales Orders = Enabled, and bidirectional synchronization is off; that combination is valid. With this setup, Microsoft states that a Submitted Dynamics 365 Sales order should first be transferred into Business Central as a Sales Order, including its lines. I would therefore treat the Sales Line error as a secondary error and check Integration Synchronization Errors for an earlier error for the same order/header; use Source/Destination and Show Error Call Stack. Also verify that all dependencies required by that Sales order are already coupled/synchronized—especially Customer/Account, Item/Product, Unit of Measure, Currency, and Customer Price Group/Price List—because Microsoft specifically states these dependencies must be coupled before Sales Order integration can work. After correcting the original header/dependency error, open Sales Orders - Dynamics 365 for Sales, locate the submitted order, and use Create in Business Central manually (or retry the automatic synchronization). I would not manually create a Sales Header just to satisfy the Sales Line error or change the table relation; first determine why the normal order-header creation failed. If other orders synchronize successfully and only this order fails, focus on this specific Sales order's customer/products/UOM/currency and its earlier synchronization error rather than the general connection setup.
Regards,
Oussama Sabbouh
