Disappointed

I had a contract with telkom, which came to an end after 24 months, I called and I told them I won't be renewing the contract. They acknowledge what I told them and they also have phone records to prove that. After the last debit which I think went off on the 31 march of 2022, they then went and debited my account R83, when I call they told me that it's for insurance and I told them what insurance because I have canceled my contract, I was told to contact the 3rd and when I did they told me I don't have an active account with them. My problem right is that telkom took my account to nudebt and they are making demands for something that was canceled in time. Worse I was advised to make disputes on my bank account by their consultant (telkom)