Notification did not go to additional recipient email added to Alert IRC_Requisition_Posted_External

Summary:

I am trying to extend seeded alert IRC_Requisition_Posted_External by adding more recipients to the alert. Notification did not go to additional emails added to the Alert.

Content (please ensure you mask any confidential information):

I added 2 additional recipients to the alert IRC_Requisition_Posted_External :

1. Static email: myworkmail@gmail.com
2. Area of Responsibility: ${AlertUtils.toString(AlertUtils.unionRep(emps.PersonId).UserName)}
   

I expect the alert to be sent to the additional recipients added but they did not receive the alert. I see the below error in the alert log:

Alert Process Started for Alert Id :[ 300000000357015] Alert Name : [IRC_Requisition_Posted_External]