The expression pedal mappings work a little bit differently in H9 Control than in Blackhole.  You can't touch and drag the expression pedal range endpoints with your fingers in H9 Control.  We intentionally disabled this because it was too hard to hit them with your finger;  in Blackhole where you use a mouse it was easier.  You can use the two buttons on either side of the ribbon cable to put the parameters in "add to mapping" mode and moving a parameter adds it to the mapping.  Touching the ribbon cable or the buttons again takes it out of "add to mapping" mode.  You can remove a mapping by double clicking a parameter and selecting the remove from mapping option.