Service suspended for no reason and waiting for almost a month for a response on the inexplicable exorbitant billing on data

I have had Smart XML contract package with Vodacom which is comprised of +/- 800 minutes, +/- 800 MB data bundles, and a some SMS. In addition, I took out 2 Gig monthly subscription. According to Vodacom, with this additional 2 Gig special, any positive balance at end of each month is carried forward to the following month. So combined, I am supposed to have a 2.8 Gigs of data on a monthly basis. Mostly, I would be left with positive balance at the end of each month. However, since May this year, I realised that my data gets depleted before the month ends. On 20 August 2017 I had to purchase an additional once-off 2 Gig data bundle. Again this data was depleted within the same month. On 20 August 2017, I logged a query Ref. No.1- ********** ********** . When I followed up on the 29 August, I was informed that the investigation was still under way. Instead I was given 2 free Gig. In September I was to be credited with my normal amount of (800MB) data as part of my subscription as well my monthly recurring 2 Gig. This together was supposed to total 4.8Gigs. for the month of September. On the 7 September I received feedback on the 20 August inquiry. Together with the explanation, was an additional offer of 2Gig for free. So all-in-all for the month of September I was supposed to have a total of 6.8Gigs. There is no way I could have utilised all of this data within September. On the 01 October, an additional 2.8 Gig as part of my subscription allocation was supposed to be credited to my account. However, by the 02 October I was informed that I have already exceeded that allocation to the extent that I had already utilised in excess of R600 out of data bundles. By the 07 October this amount had reached R902.00. However, Vodacom says I have utilised R5 800.00 since 01 October 2017. I have asked for the explanation for this on 07 October 2017. Instead the consultant I spoke to said she couldn't tell the reason because I use an open line, furthermore she could be offering me free 2 Gigs, but because I was on open line, then the system could not permit her to do so. She said this would have been possible if I had been on a Top-Up Package. I then requested that she converts me into Top-up package, effective from 01 November 2017. At that point I also asked to purchase additional once 2 Gigs, so as to prevent from going deep into out of bundle debt. This she did. On 31 October 2017 my line was suspended, and a caller line identification was deactivated. I had to make several calls into the call centre, but no-one can assist. All the people I spoke to, Noluthando in Customer Care, Akhona Noji in back office, Dati at Subcriber Collections, all confirmed that my account is up to date, but could not help. I am now without service, but my account is suspended for no reason. I am also haunted by a possible bill of R5 800 which no one can explain it,