Vodacom changes upgraded product without consent

I was contacted on Black Friday 2022 to upgrade by contract. I was offered a recurring data and voice bundle at 90% discount. It appeared on my invoice for November and December. Since January 2023 I only received the data bundle and not the voice bundle. I phoned to query and I was told it was corrected. A month later I had the same problem. Clearly your sales team is ***********, you sell customers products and then decide when you want to cancel it. Phoned again today, two people told me they cannot help me.