How can I reset the editor button to another key (fortnite)?

Question is in the title…

Currently I have "edit reset" or (rotate / repair / change case) on the right joystick (R) and would like to change it to square. Does anyone know what I have to set? I have already changed the setting (i.e. R and square) but that is not possible.

You have to go to customized settings and then square and then choose what you want on this button.

(This setting is also where you can choose master builder and something)