I've discovered that...

I've discovered that they've been deducting double money of the amount of R250+R250 from my account which I wasn't aware of and I want my money back ,I've called them and asked them why did they deducted,they told me it was because I have two vehicles but I didn't give them permission to deduct and now I want my money back,they should pay every double amount back ,I didn't authorised it