Poor service

I was contacted/notified by Cell C regarding the expiry of my contact on 11 February 2019, I called in to query my options on 2 January 2019 and was advised on a few options. As I did not want to commit to a 24 month contract, I asked for a sim card only (month to month option) and was interested in 2 options presented to me: 1) R29.00pm for 30 minutes airtime and 500mb of data 2) R149.00pm for 90 minutes of airtime and 500mb of data. I opted for the R29.00pm option but was quickly told by the call centre agent that it was no longer available so I went for the R149.00pm option. On the 25 January 2019 I called the call centre and advised that I wanted to cancel my contract and go onto a prepaid facility as I was going to take a contract at Telkom. After telling the call centre agent this he advised that I should take the R29.00pm option, I agreed and said to him that I was told that it was no longer available by the call centre agent I spoke to on 2 January 2019. He told me it was still available for a 12 month period only however I was happy with that. On 11 February 2019 I received an sms informing me that my renewal would be R149.00pm and not R29.00pm as opted for. I phoned into the call centre on 11 February 2019 and was told that it was a mistake and this should be corrected within 2 days which has not been done. I have now contacted the call 4 times to correct this matter.