Vodacom app error and unwillingness to rectify

On the 22nd of June 2020, I tried buying a 5Gb data bundle via the Vodacom app on my phone. It gave me the error that it cannot be processed and I need to try again, I tried another two times again and it gave the same error. I then received a message from my bank to say it went off 3 times. I immediately called customer care and asked them to refund me and take the extra data. A call was logged and I was told to send proof of payment which I did. There was no further communication from Vodacom and I tried contacting them again with no success. I have sent numerous emails with no reply just a automated message saying a ticket was logged. 3 months later, I received a call from a rude agent by the name off Bertram Cupio who basically shifted the blame onto me and was not willing to assist even though Vodacom was at fault. This data would have expired in 30 days and I requested the data to be taken off my account as Vodacom delayed in resolving the query but Bertram insists that only the extra data which came through due to their app issues could be refunded. I was furious with his lack of customer service as well as a bad attitude. In my opinion, he gives Vodacom a very poor image and did not even say let me see how I can assist you, he outright did not want to assist!!! How can Vodacom not take responsibility for a glitch in their app and knowing there was a problem from their side not be willing to assist? Furthermore, there is a lot of data on my account which can be taken to accommodate the data which was unwillingly purchased through the app glitch, why can't it be used? I would appreciate if someone with customer service skills can contact me as soon as possible without having to wait another 3 months which is ridiculous but with people like Bertram employed in that department, one can see why the service is so pathetic. If Vodacom cannot resolve this issue and deal with their poor customer service, I will take all my contracts to another service provider.