Unknown contract under my name

Last year I went to vodacom shop to enquire about their wifi routers, i brought payslips and bank so that they could check my creditworth, it ended there, the next thing the was debit order deducting in my bank off which i reversed because I knew nothing about it. I was told by the bank it was vodacom who deducted. I went to vodacom shop in king williams town for enquiry, they discoverd that the device is still with them, but I couldnot get answers as why I am billed for services that I am not enjoying. I emailed a Copy of my id with 3 signature on with affidavit and bank statement to *****dispute@vodacom till today the is no assistance received, all I receive are calls from vodacom accounts section wanting me to pay. Please come to my rescue.