MTN black friday deal go terribly wrong

We had Extremely bad black friday deal experience with MTN. After 10x calls to the call centre for help how to to do sim swap and 5x visits to the MTN branch all with failed attempts to do the sim swap. We decided to cancel the black friday deal we took, we phoned the call centre again 5x times and noone knew how to cancel it, MTN send me a invoice today. We very disappointed in MTN and will never recommend anyone to take out a MTN deal through the call centre or on black friday.