Error message on Warehouse Management app: 'An update conflict exception occurred. Please try again in a few minutes.'
This error message means (from our experience) that the deadline date for the return order has been exceeded and/or the original sales order "Requested ship date" is in a financial period that is not open.
To resolve, the dates for either deadline or requested ship date needs to be modified on both return order and/or original sales order, so that the dates are in the present/future and in an open financial period.
This is usually reported by Goods In from NDC and then solved done by Internal Sales/Customer Service.