HRHD: Creating email notification when SR is put into 'Resolved' status

Summary

We need to fire an email to notify when an SR is resolved

Content

I am trying to create an object workflow to fire an email when an SR is updated to Resolved status. I have created the email template and attached it to the workflow. The event point is when the record is updated but I believe my solution is not working based on the condition I have created (see screenshot or below)

if(isAttributeChanged(StatusTypeCd) && StatusTypeCd=='RESOLVED')
return true;

This is causing no notification to be fired. I have also tried the condition:

StatusTypeCd=='RESOLVED'

But this just sent a notification when any update was made on the SR.