Bad customer care

Telkom mobile is absolutely disgusting, I have a cellphone contract with Telkom, In so many attempts I tried to contact their so called customer care department to change my debit order details one their contact Centre consultant told me is impossible to do so, last month I was charged just over R200 for debit order rejection and this month also I got charged another over R200 for the same.Their accounts seems to not care about that and I'm not going to pay again the R200 this month. And I want my money back or else I'll take further legal actions.