Unauthorized upgrade, without the cellphones

December 2017 I took out 2 contracts for my grandsons. June 2019 Vodacom phoned me to upgrade. According to my memory I spesificly said that the upgrade is only due Dec and would not be interested. I enquired about the upgrade in October at our local Vodashop and they informed me that the contract had already been upgraded in June and that we will only be able to change the contract 18 months after that. I have phoned Vodacom 5 times to date to request the phone recording of that conversation. I was initially told that the recording will be sent to my local Vodashop and that I can listen to it there. I contacted the Vodashop and the manager confirmed to me that nothing had been sent to them in regards to these contracts. I phoned again and was redirected. I phoned again twice and both times I was told that the supervisor needs to listen to the voice recordings but that they will phone us with feedback that same day still. It is almost a week ago, still no feedback and no recording. I phoned them again today, was on hold for almost 11 minutes, and when the guy finally picked up he just cut me off. My issue is that I specifically asked not to be upgraded because the phones are Christmas presents every 2 years and I did not want the phones 6 months early and they are already older models by Christmastime. However now that I want to upgrade I am not able to. I can not prove what was said during the phone call without the recording and there is no signed paperwork for this alleged upgrade for me to refer to. I will be stuck with 2 contracts that I did not want, without the phones (as I have not received any phones for this alleged upgrade) for a further 2 years.