Union for 2 reports

Summary:

How can I combine the output of 2 reports into one output

Content (required):

I have two reports, both using the same 2 Subject Areas (Workforce Management - Worker Assignment Event Real Time & Workforce Management - Workforce Trend Real Time) and the difference is just a filter on one of the reports. Can I combine these two outputs to display on the same output?

I have tried to add a UNION on my analysis but when I try to select the Subject Area it is not available.

Version (include the version you are using, if applicable):

22B (11.13.22.04.0)

Code Snippet (add any code snippets that support your topic, if applicable):