Deducted double payment without consent

I bought 2 cellphones on contract by Telkom but to date i have not received a copy of my contract,i did my sale telephonically but when i went inyo the store in Promonade they could not find my details on their system ,i tried to make contact no response from them.They deducted double payment last month,mobile device is problematic have to charge every 3hours,switch off and freeze,if you type a number to dial the numbers jump and after that dial the ladt number you dial,i need a copy of contract,dont want double deductions out of my account made without permission of me ,please assist