Billed for Contracts that was not authorised

Hello,

I did a sim swap and switched to CellC this year. I called the CellC call center and requested a data contract and a voice contract. They requested documents to be sent to them, however, the email kept on bouncing back as undelivered. So I decided to go to a store and get a contract there and not take the data contract as I could not send the documents to them. While I was out the office one day, a few sim cards were delivered to my office. I never used them as I already had a working CellC sim. The following months I noticed that 2 debit orders went off my account. I called them and requested that the 1 be cancelled and all fees to be reversed. I sent them a message on my app as well requesting the above. I got a response stating it will take 24-48hours for a response. Still no response..... Poor service!