Telkom add random contracts to my account

I have just received a debit from Telkom that is more than double my normal debit. I logged onto my account only to find that there are 3 additional contract added on - contracts I have not app**** for. I contacted Telkom - they indicate that I should now supply a whole host of documents to prove I did not open the contracts before they will investigate. My view is this - their verification systems should be robust enough to stop this from happening - if this is a failure, the responsibility lies with them to sort it out. Additionally, they don't have my signature so the contract isn't legal in the first place. I will now cancel reverse the current debit, cancel the debit order (because clearly the bank allows then to debit any amount they please), and pay them the actual amount I owe them. This is really poor from Telkom - they should know what an issue ***** is and have proper verification systems and proper recourse for customers should there be a slip-up on their part.