Vodacom charging for services to utilized

A debitorder of R5679.51 went off my account on the 31st of January. I reviewed my invoice and found that Vodacom as charged me R3102.61 for data roaming for the Dec 2019 invoice. This came as a big shock to me as I never used data roaming in December 2019. I did travel to Mauritius on the 24th Nov 2019, returned to Cape Town the morning of the 1st Dec 2019. My data roaming charges for 7 days in Nov was R2077.39. I flew back to Cape Town the morning of the 1 Dec 2019. Do the maths.... I reported this to the call centre on Monday, 3 February, after various phone calls an agent phoned me on the 5th of Feb to inform me that they will credit my account with R1700. I did not accept this offer as I did not use data on the 1st of Dec. My phone was on flight mode while at the Hotel the morning of the 1st Dec and I only turned my phone back on at the airport where I used the WiFi. On the 3rd of Feb I received an email from Fatima Isaacs who is in back office in the "Advanced Data Support" division. She emailed me a data roaming report for the period of 1 Jan 2019 tot 11 Jan 2019. I was in Cape Town during that period, how could I have used data roaming??? She informed me that she will escalate this further and phone me on Monday the 10th Feb. She did not phone me, I phoned the call centre 3 times on Monday 10 Feb and left messages for Fatima, no response, I phoned again on Tuesday, the 11th of Feb, no response and still waiting. . . . . . . In the meantime I also discovered that Vodacom billed me (without my knowledge or approval) for R115 a month for data on my son's contract which I pay for. We never agreed to this as this was never part of the original contract and we have Wi Fi at home. I also discovered that I've been billed for R52.17 on a contract which we cancelled with Vodacom last year August already. Vodacom has a reputation of ********* behavior and charging customers for services not being utilized.