Big company...can't even refund me

I was at the end of my contract and decided to end it..phoned them got the email confirmation about a month later realized they still deducting phoned them again cancelled it again...now I want my refund. Got the conversation that it is being escalated. Still now refund...phoned again..according to the system nothing. Did it again....still no refund for money deducted for 3 months. Phoned them again and the lady couldn't see anything....now what now...? Still got other contacts...but have to go the time left on the contract.....Will the same happen when I'm going to cancel? That is why Vodacom is getting my bad review.