Vodacom ****ming people with only sim contract phone calls

I bought a contract phone with vodacom 2020 and when I finished paying it off I took another phone as an upgrade 2022 which I payed off and my contract was supposed to end August 2024 when I finish paying the phone off. Around March or April 2024 a lady called me offering me an upgrade and when I told her I don’t want another phone she insisted that the upgrade is not a new phone and it’s to save me on data consumption as I’m currently spending a lot on data. And as soon as she said that I agreed so that we can finish the phone call and go back to my sleep. Now I’m done paying off the phone and I’m forced into a only sim contract for 4gig data and 400 minutes at R680 per month. I have called and been to vodacom multiple times to tell them I’m not interested in the contract but they just ignore me . The manager from vodacom sandton city mall Mr Mabasa called and sent multiple emails to vodacom telling them to release me from the contract as I have zero interest in another contract, he is just being ignored by vodacom for a month now.my question is if didn’t come to the store to purchase your services why do you call me in my free time to **** me by partially explaining a service and convincing me to buy it when I never showed interest from the begin. This is ***** because you’re trying to up your market sales by forcing people into contract all because you get commission from it. In the first place the only reason we choose some of those stupid minutes deals is because when you buy a phone you’re forced but now to force me into one when I don’t owe nobody?

Please kindly help