WHAT THE HELL VODACOM???

I took out a 24 month contract in December 2017 that included a wifi rooter and 20G day and night owl. Since October 2019 I have been phoning as I wanted to cancel this contract and NOT upgrade. I was told that the contract only ended in March 2020. Since I opted not to upgrade, my monthly installment increased. So again I tried to phone in December, unable to get through. On the 3rd of January, after 40 min, I finally got hold of someone, and all she then said she will refer the matter. Phoned back, and same answer, contract only ends in March 2020. My january invoice states my monthly installment, has no increased from R352 to R1007. On the 10th of January, I emailed the complaints department. To date no reply back. So again I phoned on the 15th of January. The lady assisting was more interested in the party going on in the back ground and laughing with her colleagues, that she was did not listen to my query. The noise is so overwhelming I don't know how you expect to deal with customers. Again I had to hear that the contract ends in March. I tried to explain, that I signed a 24 month contract, how is it possible that it expiereds in March only, 27 months later??? she then told me the promotion ended in December 2019, and I did not upgrade. Now I am paying for the device. Suddenly she was could sent me an invoice with another amount of +/- R690 that will be deducted over the next 3 months in installments of R230. Why was the modem not included or deducted over the 24 months??? this was not what I signed up for. Had that been the case, I would never have taken this contract. So either the person selling, or the person invoicing, is messing up. I am really not interested in any more excuses. I want this contract cancelled, as it was suppose to be done in December of 2019 already. As the customer, I did my part, I phoned, I followed up, I enquired, I knew this contract ended and that I had to cancel a month prior, which I tried to do, but repeatedly was given the incorrect information. I have a choice to upgrade or not, and I made the decision not to do so. Now it seems I am being punished for not doing that, with a pathetic excuse of having to pay for the modem!!!! This is nonsense and the first ever I hear of such a contract. I have been with Vodacom for over 20 years, and never ever did I have to extend a contract to pay for the device after the expiery date. The device and data plan is included !! So fed up with Vodacom and their imcompetent staff that do not know how to deal with customers