Unauthorized debit order

I started getting debit orders from Cell C a couple of months ago. Iv never had a cell c product in my life so naturally i stopped and reversed all their debit orders. I decide to call them and find out why they are taking my money without my authorization to which they told me i opened a cellphone contract with them a couple of months back. I was then told that i need to go get an affidavit from the police, along with other documents they required, in order to stop the debit orders. I refused because i dont want to go up and down to resolve an issue i didn't create. I then ask for the FICA documents used to open the account to which they refuse which doesnt make sense they are "my" supposed documents. Im then told that if i want the fica docs i need to go get them at the cell c store the contract was opened at, Cell C Woodmead (iv never been). I then call Cell C woodmead and ask for the docs and they say the contract wasn't opened there but done telephonically. I then call cell c again and ask fro the FICA documents and the recording of the contract being opened to which they refuse again and ask for a police affidavit before anything is done.