how to restrict an analysis to 1 assignment

Content

In our HCM setup we can have people with multiple assignments which are active. What I want to do is get the most current/latest assignment. The primary flag does identify which assignment is primary, but in the report I am building I need to only return the non primary assignment  for those with 2 assignments and the primary for those with 1 assignment.

I was able to accurately return the values using the MAX("Worker"."Assignment Number" BY "Worker"."Person Number") filter, but when I then filter the report by prompts for Department if the person's 2 appointments are in different departments then the person shows up in both departments data sets when they filter by Dept. Any assistance would be appreciated.