*****: Unauthorized contract against my name

I am an old Cellc client, I called Cellc to do a Sim swap only to have them register a new contract on my name and they deducted double the amount I am used to paying. I called them to complain I was advised to write a formal complaint with a affidavit and bank statement attached, I did that about a week ago and nothing had happened up until now and when I call their ***** department 061 000 700 the number does not exist. I am extremely disappointed at this bad service. We are now approaching another pay date and their obviously going to deduct double again for nothing I don't know about.