I hope you crossed the 3.4.1 section of this learning path
There you created and entity named as SLAStatus and an attribute which is of enumeration type named as SLADashboardStatus
As per the 3.4.1 section of the learning path the name of the attribute is SLADashboardStatus but later in screenshot they shown with underscore in between the attribute name like SLA_DashboardStatus.
Can you try this one : TaskTracker.SLADashboardStatus.SLA_Achieved
For your information: Here TaskTracker.SLADashboardStatus.SLA_Achieved , TaskTracker is your module name , SLADashboardStatus is an attribute name and SLA_Achieved is nothing but one of the enumerated value of that attribute.
I hope this will helps you
In the SLADashboardStatus attribute of the SLAStatus entity, create a new enumeration called
TaskTracker.SLADashboardStatus and create new Enumeration values called SLA_Achieved and SLA_Missed (fill in same value for name and caption).
Then in the microflow, you can select these values in the member field of the change object activity.