Can you please check the Doc ID 1929340.1.
As per the note it is confirmed that PO approval workflow -Web Supplier Notification is called ONLY when the PO communication method is set to EMAIL. This Web Supplier Notification will not be called if the PO communication method is set to NONE.
In you case if the PO communication is set to None then it should have not sent the notification email to supplier. You can update the SR with the above note and check on the conflict updates.
Thanks for your comment.
Yes you're right. It does behave so when creating Purchase Order. However, the ER I logged is pertaining to 'Requester Change Order' (RCO) workflow.
Despite of PO communication method is set to NONE, when user performed amendment in iProcurement (via Change / Cancel button), after buyer approved, a notification will be sent to Supplier.
We assume the logic should work this way, as long as the communication method is already set to NONE in original PO, hence the RCO workflow shall follow PO communication method value (i.e. NULL), no notification shall be sent to Supplier. Otherwise, supplier will be confused while they did not receive any Purchase Order in the first place, days/weeks later they are notified PO has been changed/cancelled.