Problem
I can't add items to a purchase order made from a requisition.
Solution
Create a new PO and use the updated requisition with all items included.
Updating and reprocessing a purchase order
Cancel transactions the Pending Purchase Order (PO). This returns the items to the requisition list.
Go to the requisition list. Find the requisition you worked on.
Edit the Requisition. Add the new items you missed.
Assign the same procurement source and shipping info. Do this for all items, new and old.
Create a new PO. Use the updated requisition with all items included.