I'll treatment by Vodacom

I recently bought a new contract with Vodacom they delivered the phone but did not deliver the SIM card and they overcharged my account. I have called for several times and the call centre agents will each time I call refer me to their supervisors whom they will come and promise to sort my issue. It's been over three weeks now no SIM card delivery and my account has been overcharged. For more than a decade I have been with Vodacom with more than 3 lines but am being **** to and treated as the thrash. Vodacom is no longer the same on us their customers and I now regret my decision to choose them.