*****lent and Unauthorised Mobile contracts added to my account

I have recently discovered that someone **********ly added two mobile contracts unauthorised on the 22 of October on my behalf without my knowledge nor authorisation to my main account with Vodacom. Upon finding this out (after having had two exactly same amounts debited to my bank account), I reported this and on the 30 of November sent the required documents to the Vodacom ***** Dispute email address and to date I still have not had any feedback. Upon logging the first call and sending the documents, the second number has appeared, hence I am now sitting with a bill so far of R3689 to be paid, which I do not have the money to pay. What I do not understand is that with all the security questions etc we have to answer, how did these individuals manage to add these 2 contracts to my account??? Shocking to say the least!!!!!!!