Nestar terrible tratment of their customers and poor communications

I had a contract with Netstar for 24 months and I continued with payments even beyond the contract .on a month to moth basis. I was involved in an accident in April 2018 and I called Netstar on the 2/05/2018 at 9:50 AM and talked to Mbali requesting that they cancel the contract, she gave me ref: no: CAS ********** . On the 1 June an amount of R112.21 was deducted from my account. However they continued sending messages and calling me that I owe them R224.00, with no invoice and now they have submitted my name to Hybrid Collections (Pty) Ltd . I have tried on sevear occations to send emails to their customer center with no response.