False Advertising - Told an upgrade was due when it still had 3 months to go!!!

I was contacted in December 2019 to be told that an upgrade was due on one of my numbers. I declined it. Then I was contacted on the 17 January 2020 to again let me know that an upgrade was due. I was told that there was a special on for 10G Anytime Data and 10G Nitetime Data in the amount of R149-00 per month. I was told that it was available immediately and that it would be pro-rata'd until end January 2020. I received my bill today and almost had heart failure ... my bill for that particular number came to R471-24. The pro-rata amount was R134-64 for 13 days. The new month, however, (February 2020) was R471-24 less what they call Discount access of R223-34. I am now expected to pay the amount of R247-00 instead of the R149-00 as quoted. When I contacted Cell C today, they told me that the monies due was because my contract was still in force and I had taken an earlier contract .... why was this not told to me??? I would not have taken the special on that date. I would have waited until my contract had actually expired. Why is Cell C not telling their customers about the earlier contract??? I would like Cell C to go and listen to the call recording. I am placing on record, that should this not be dealt with immediately and an answer given to me as to why I am contacted 3 months ahead of time to let me know that my upgrade is due ... when it actually wasn't because I still had 3 MONTHS to go!!!! If this is not sorted out, I would like the contract to be cancelled with immediate effect as it is in breach as my contract was NOT DUE as yet. I am contacting my lawyers as well to see what I can do about this. I am also asking Cell C to not contact their customers until the contracts are ACTUALLY DUE FOR RENEWAL!!! I am awaiting your response soonest. Regards, Ann von Brandis