Cellphone contract Regret

We had a great relationship with Vodacom for 24 months but the problem started when the contract ended in October 2020.i was getting 175 minutes every month so end of October last year on the last payment I cancelled the contract. However it was not cancelled. I kept on calling the cancelation line every month telling them our finances does not allow us to continue with the contract. We are now in March and it's still not cancelled. I'm getting calls and sms saying I'm owing vodacom. I seriously don't know what to say or do anymore. I regret taking a contract with them