Poor customer experience

In May i was incorrectly charged for a data usage and i spoke over 5 cellc managers. They offered me a 50% reduction on the charge. I was very upset so i spoke to a guy called Brandon Victor he told me he can offer a 50% reduction and thats the only thing he can do the charge was for R1000, which Cellc cant tell exactly what is is for , when i told him okay i will except the 50% reduction he said no i wont give you the reduction because you screamed and you were swearing me last time he said you cant do nothing and he said F***k you and dropped the call and sent my account to the leagal department. I then called the C.E.Os office and spoke to the P.A (Angela Nail ) she said that she has him in her office she will investigate the issue and call me, 2 months later no call i called to speak to her but i had no responce she called today (22/06/2015) and said that she sent an email to Brandon Victors manager to call me. When i first spoke to her she was so helpfull now she is calling me a lyer saying she spoke to Brandon and he says he did not do that. Why did he call from a line that Has no recording if he did not do that. This is the 3 problem with Cellc ,no customer experience