Poor Service

As with most companies after sales service vastly differs from pre sales, this is yet again another case in point. After upgrading my alarm system (happy with that part), ADT started overcharging me. I lodged a complaint and with some effort, meaning me constantly calling them, the problem was identified and corrected. However they owe me a credit, a nominal amount I will agree but after 3 weeks of me yet again constantly calling about this credit, I receive the same feedback, "it has been escalated" and "some one will call you back". Needless to say no one calls me back, perhaps ADT thinks I will go away but I won't.