You can add an incident in the individual order page.
Go to Execution.
Click on the pencil to edit the trip in Route.
Click on the dropdown Incident and complete the reason of the incident.
Save it.
Once saved, you will see that the activity will change to the reason of the incident (e.g. Failed delivery).
On the order list, you will also see a tooltip indicating the reason of the incident.
You can also see the incident on the trips page: