Deleting an open Purchase order (PO) removes it from the Buy screen and eliminates the respective Expected quantities for related materials in the Inventory tab.
To delete a PO:
Navigate to the Buy screen and find the PO in the list. Click on it to open the PO card.
Click on the 3-dots at the top corner of the PO card and select "Delete" from the drop-down menu.
Click Yes in the pop-up window to delete.
Caution! Deleting Received Purchase orders decreases the In stock quantity for the relevant materials in the inventory list.