Not customer centric at all

I'm very disappointed with the Supersonic accounts and the customer service. My bills have been a disaster every month, either it is extra or less and then when I phone the customer consultants are very confused about the bill and would then refer to the manager. The manager would never call me back to clear it up. Up until now they owe me a credit of R249 for my bill for December but according to accounts I owe them R107. Nobody and assist me when I call and I just don't know what to do anymore. All I want is for somebody to look at my December Bill and correct it. The consultants are not equipped to handle accounts queries and the accounts people cannot be called. Supersonic please do something