Regenerative braking doesn't work

I have a problem with my GEM elxd of 2011, I have no regenerative braking.
I try to put function 19 and 20 to 128 and I have a connection between the pin 12 of the controller and -72V but nothing

Regen is a complex relationship between several function settings.
In addition to 19 and 20, you might want to give 9 and 10 some tweaks.

Is your connection to p12 a permanent fix? Or momentary like a push button?

Do you have any speed modifiers attached to your speed sensor? (is your speed display accurate?). These will also affect how regen responds.

it’s a switch so when it’s active, it’s permanent

I have the OEM system of the speed sensor and I have no problems with the speed display