Problem
You cannot edit or add a PO to a posted or exported invoice.
Solution
Enable adding or editing purchase order on a posted or exported invoice
The capability to add or edit a purchase order (PO) on a posted or exported invoice requires a change to your account configuration. You will need to have Administrator permissions in order to make this change.
Note: Account configuration is required to access the Feature Configuration screen. Contact Technical Support or your Customer Success Manager (CSM) for more details.
In the top toolbar, click on the Settings
icon.In the left side menu, click on Your Account > Feature Configuration.
Type Purchase into the search bar.
Find the feature configuration name Hide 'Add a Purchase Order' Option on Posted and Exported Invoices.
Toggle this configuration off by clicking the button next to Enable.
Add or edit a purchase order on a posted or exported invoice
Search for and go to the posted or exported invoice you want to add or edit a purchase order to.
On the invoice record:
To add a purchase order, click Add a purchase order and proceed in completing a purchase order.
To edit a purchase order, click Edit
on the purchase order in the Purchase Orders section of the invoice and make edits to the purchase order.
When finished, click Create or Save.