Telkom rips people off

Telkom seems to rip people off. Imagine having a R100 contract sim only and then still paying extra R20 because they charge you R120 but the contract states R100 , then you call in to change your payment date but it doesn't happen, so I called again and again and again ended up calling twice for past 4 months and now they charging me extra R180 for late payment that was their fault, asked if I could cancel they tell me cancellation fee is R900, How ridiculous can you be. TELKOM IS *****