Busisiwe Tshabalala MTN Westgate Shopping Centre

MTN WESTGATE SHOPPING CENTRE!!! I requested to cancel a contract last year(2023) September, i gave them the router back. They gave me the reference number and irms number and it was confirmed that the contract is canceled only to find out this year march that the contract is still active. I got an invoice and i paid only to find out that I paid for something that was supposed to be canceled long time ago. The store at which i canceled the contract are refusing to help me. The lady is Busisiwe Tshabalala at MTN Westgate Shopping Centre, when i call the call center they say i should speak to her. But her and the manager at the store are refusing to help me. I'm very frustrated as I have paid money (R791) for something that I'm not using.