Unwilling to resolve my account query

I have tried numerous times to resolve a R400 spike on my account billing, the first couple of calls I made I was simply ignored. Leaving me to resort to social media. I received feedback days later saying that the R400 spike on my account (which took place in under 10 minutes) was I result of my apps running - I had done nothing different that morning so the gentleman advised that he would get Moses Mo***eng to explain the technicalities. Later I received a call from him & now I was being told that the R400 spike was a result of my phone's OS upgrading. Again, this appeared misleading. When my OS updates I get prompted for consent, the upgrade takes at least 20 minutes to download and install, my phone reboots & there are visible changes - of course none of this had happened. He then proceeded to tell me that MAYBE my sms codes reconfigured resulting in the R400 spike, & that I would never know the difference. He then said he'll send me a report which would explain exactly what he was talking about, however this report would be so confusing that he would need to explain it to me, & I should email him as soon as I received it. I did this and his response was \ this case is closed""""