Matrix Overarching Header

Hello,

I am trying to create sections in my matrix view but cannot find a way to make it dynamic. If I create text boxes above the sections it obviously won't adapt if a filter is applied or the drill-down feature is used. 

This is how I want it to look. Is there a way to get the words "P&L Details", " FY23 Selected Periods", and "FY23 Whole Year" to be used as column headers for a section? 

Thank you,

Kristina