The article outlines the steps to change the purchase order vendor
FOLLOW STEPS BELOW:
1. Click "Purchase Orders" -> "PO's"
2. Open the PO you want to edit (use Searching and Filtering if needed)
3. Click the Vendor "Drop Down" button
4. Select the new Vendor
5. Click "Close"
6. Click the "Refresh" button
NB. For a quick tutorial watch below