Rude Staff

I received an email after settling the debt with ADT . Since March I have been trying to call Norman Bisset to inform them of such The staff is rude and just dropped the phone on my ears I just found out that I have been listed but according to ADT there is nothing owed . I need to remove this negative listing from my Credit Report but no one is helping Today I have been on the phone this whole afternoon and have all my 4 calls dropped