No success regarding cancellation of services

I have taken up a contract with Vodacom verbally in January 2013 when a lady from the service centre called advertising the contract. I do not recall ever signing up or agreeing for additional services such as elite mobile services. I was only made aware of these services when I looked at my bank statement in December 2013 and realised that there were four debits with the reference EM coming off my account as well as Milc services. I successfully cancelled milc services and they advised me that the other debits related to elite mobile. Thereafter I contacted elite mobile and cancelled the services and they assured me it will be cancelled. January they debited my account four times and I did not have funds and I incurred bank charges of R115 for each unpaid debit. In the middle of January they debited again and the same thing happened. I contacted them again and cancelled it again and still in March my account was debited. In April or May I called again and stated my ID number and was told that there are no services. I then gave the reference number and the picked it up & assured me it will be cancelled. In the month of August debits came off my account. I am know helpless & tired.