Vodacom can't cancel a contract

I am very dissapointed in the service (or rather lack thereof) I have received from Vodacom in the past 3 months. I contacted Vodacom cancellations per phone on 9 May at 15:00, where the lady persuaded me to rather change to a cheaper contract than to cancel my contract. This would be implemented from the 1st of June, which didn't happen. I gave it another month, to see if it was an error, but again the full amount was deducted from my bank account at the end of June. I phoned again on the 30 June 09:30 and spoke to Phindile and Byron (I could not hear the names properly). I asked them both to cancel the contract and switch it to pay as you go. They placed me on hold while they did this. I was on hold for 17 minutes and the second time for 8 minutes, whereafter it went over to the rating message. I gave a very poor rating, as my query was not resolved. They did not speak to me again to confirm that my contract was cancelled. After this I phoned the cancellations AGAIN at 10:13 and spoke to Vossa with reference number ***2. He confirmed that the cancellation was not captured on the system and continued with the cancellation. He confirmed that my contract would stop from 1 August. However, the full amount was debited form my bank account on 27/07/2020. Since Vodacom record all calls for quality purposes, I urge you to investigate this matter since the employees clearly didn't do their job. I am fed up with this service. I get the impression that the consultants don't want to cancel a contract as this reflects poorly on them. I expect to be refunded for the R508.11 for the 3 months that I have been trying to cancel this contract. I await a reply from Vodacom.