Bug in Notification System?

A strange thing happened today.

I have a SMS notification system set up using the built in Notification in ERPNext v13 (self hosted). One of the SMS system is to send sms to supplier with summary of items and quantity on submission of PO and another SMS is sent to the supplier if the PO is cancelled.

Today, one of the suppliers called me and asked why an older PO was cancelled. I checked the PO but it’s status is not cancelled. I checked my SMS portal. It shows sms sent via API. But no where in ERPNext is the record of PO cancelled. Even in Notification Log, there is no record of SMS sent. But both the supplier and my SMS service provider’s portal show record of SMS sent. The PO itself is not cancelled.

Later I found out my employee was creating purchase receipt for the same PO. Purchase receipt was made but somehow PO cancelled sms was sent. Please note, there is no sms system set for purchase receipt. The employee also got an email saying Energy point reverted because PO was cancelled.

Screenshot of SMS providers dashboard

Screenshot of SMS alert settings on PO cancel.