Device Parameter ON/OFF

Hi,
thank you very much for this very powerful application.
I am using ableton live 11
I have a problem controlling the parameter of a device when it is an ON / OFF button
No worries to control a parameter with a knob with values ​​from 0 to 128 but what to do when it is a switch ?
I assigned the parameter to a button. This switches to OFF but impossible to switch to ON.

In my example the knobs 5,6 and 7 activate respectively the octave, the fourth and the fifth in my harmonizer (Quadravox) and the knobs 5,6,7 control the volumes.

Can you help me please ?

Thank you very much for you help.

Vincent