Debit Order withou purchase/ VVM Debt Collectors

I am a victim of HOMECHOICE /FONECHOICE **** . on the 25 september/ 21 october/20 November 2015 an amount of R783.00 was deducted in my account for FONECHOICE . i then asked the bank to do reversal which is costing me. it was a start of my nightmares , i have been receiving calls from their agent asking for payments , i told them i had no idea what they are talking about . they told me i bought a Laptop and mobile phone , address used is not mine .they are using surname NTULI which is my ****en surname , i am NDLOVU now for almost 6YEARS . Idid not received any of the statements as acknolwedgement of my debt , Recently i received sms from VVM Debt Collectors telling me my account has been handed over to them due to non payment of R6836.06 , My name is on credit bereau as we speak for something i did not do . i have been communicating with them via emails and calls but no clear response , they said they are investigating but i dont believe that , how come my name is on credit bereau ? PLEASE ASSIST ME , I AM STRESSED AND CANT COPE AT WORK !!!!! FONECHOICE *** , VVM Debt Collectors *** .