They already have in excess of R3K of my money

On 17/2/15, I noticed a debit on my bank account by Vodacom. On 18/2/2015, I mailed the customer services to inform them that they must repay the money as they already have a credit that they must first use before any additional funds are paid by myself. Needless to say, I have just got off the phone after numerous e-mails going back and forth, with about 10 different consultants, to discover that no refund request was ever logged. It is more than a month and every few days, when I follow up on my query, I am asked to verify my details and provide some security information. Might I add that the e-mails are all in one conversation, so, my details are there and verified. Clearly nobody bothered to scroll down and review the entire conversation. I further rep**** to the last mail I received and requested that a Manager call me. It is almost an hour later and still no call has been received, nor has my telephonic conversation with Nomsa been a great success either. She promised to send me a reference number for my query and request and I have yet to receive any such information.I must admit, as soon as this contract is finished, I am severing Vodacom. I am disgusted with the service.