Row Subtotals - Locked

Hi,

I am fairly new to PBI so sorry if this is an easy question.

I have a  P&L Matrix report and now I want to add a Subtotal that is CM1 - and I can see previously its been done with row subtotals and appliy per row level. However since I added a new row (Mapping column) the CM1 is now named EBITDA and the actual EBITDA is named Total.  And when I am trying to change the name per row level every row is locked except all.

I´ve attached 2 snapshots where you can see my problem.

In short - I want to change the EBITDA label to something else but its locked.