Refund on the contract that was cancelled last week

I have been calling and email customer for my refund on the money that was debited from my account for the contract that was cancelled. I took a contract for the home internet and I discovered that there was no coverage in my area - so I could not use the data. I was advised by Vodacom to cancel the contract in a space of 5 days (after signing a contract). I did that and they said I will get my refund on Monday. Its Friday today and I still don't have my refund. I am sending e-mails and calling customer with no response. Can I please request Vodacom to refund me as they took the router back but not giving me back the money and I have tried so many channels to follow up on this with no response.