COMPLETE IGNORANCE AND NO CUSTOMER CARE

I have been calling countless times, I always get the same response that people will get back to me with my issue. My account was supposed to be cancelled last year already. Riziah the manager keeps making empty promises that she will send me a cancellation letter but she never does. I have proof of the emails she has personally sent to me and I do not understand why this is taking so long after countless efforts. Now I am getting billed an amount of R186.11 which I never agreed to. Please get this matter resolved ASAP!