MTN making me pay for what I'm not getting.

I took a Nova 8 contract at MTN November 2021 in 2022 I was called by an MTN agent offering me bundles contract which she said it is 89 for 10 gig and 50 minutes in total I was paying 471 to MTN 2023.

November the contract came to an end December 2023 my bill was 251 I didn't understand why because I was now expecting to pay 89 for bundles but I didn't follow up as I thought I'm maybe paying something I don't know I thought it would only be for that month January I'm getting a bill n it is still saying R251 I call MTN they say I'm paying for two Sim cards the lady was telling me about a 2 gig and 25 minutes contract I have which I don't know about I explained to her I don't know about two gig she dropped the fone.