ADT Security - exhorbitant call out fees

To be fair, the overall service has been satisfactory. We cancelled our contract with ADT though because they are over-priced compared to the competition in our area. Our new service provider wanted to install their radio today but were unable to because ADT changed the installer code on OUR hardware. ADT will not allow you to reset this code over the phone but insist on charging a R570 call out fee to reset this code which takes a few minutes which is exorbitant! If their code is to remain a secret, would it not be a better practice to reset this upon collecting their radio?