Unauthorised Debit Order

At the end of March, I called the Multichoice call center to take advantage of their special where you pay your fees for the entire year. I was told there was some sort of glitch on my account and so I would need to do an Eft of R8569 and they gave me the banking details. I did the Eft. Suddenly on Saturday, i was called by my bank to say my account is in overdraft. I could not understand why so I went online to check and saw that Multichoice had debited my account R9284. Firstly, I never gave them permission to debit my account and secondly who knows where they came up with that amount. I called the call center and was told it would take seven days to get my money back. What a cheek, they take your money then and there, but want you to wait a week for a refund. All the while, I am in overdraft and have no money to buy food to feed my family!!!! After getting angry, I was told to call my bank and get a refund. So after all that, I must sit on the phone and fix their mistake. Unfortunately, I had no choice, as we needed the money. This has made me so angry that if they do not do something, I will cancel my contract and they can give me all my money back. Disgusting!