Vodacom refusing to cancel contract despite my request and settlement of account

Vodacom refuses to cancel Service, despite my request and after paying the settlement amount. I sent this email to them: Please find attached documents for processing of my contract cancellation. Please note that i do not want to retain any of the numbers on prepaid. I would like a full cancellation. Kindly send me confirmation of contract cancellation. (The documents were proof of payment, early cancellation form) and ID copy. This was on 24 July 2025. I asked for confirmation of cancellation that I never received. Despite all these I received an email indicating that my numbers in question were converted to prepaid which went against my request. Yesterday (08 August) I received an invoice. I don’t know what this is for. I feel so violated. My experience with Vodacom has been a very bad one I must say. I really need help.