From fellow MVP Mahmood Alsaadi: Dynamics GP Essentials: Sales Order Integration–Sales Person and Territory are not populated to Line Items
Dynamics GP Essentials: Sales Order Integration–Sales Person and Territory are not populated to Line Items
Sales, Purchasing & InventoryDevelopment & Integration
Archived post from 2015. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.