User unticked obsolete for a deleted item and that part does not generate on the demand planner or order planner.
Enabling the system parameter 'Full Refresh After Plan Save' from Orchestrate System Manager resolves the issue; performs full refresh after saving the plan, to prevent attribute changes going out of synch. Please complete the following steps:
Log into Orchestrate System Manager
Select File
System Settings
Select planning tab
Scroll down and click On for 'Full Refresh After Plan Save'
Click OK
Select File, Exit
