Misrepresentation of terms and conditions

I prebooked and paid for a rental from 1-4 October. On arrival, I asked the sales person, Kenneth, if it is possible to reduce the booked days to 3 in stead of 4 since I was only taking the stupid car for 3 days and one hour extra. He said, bring back the car before 10am (it was booked out to me at 9h41) and I would only be charged 3 days. SO basically I did bring back the car at 9h45, which was then booked back on the computer at 10h06 since the Cape Town branch is very busy. They are also too busy to attend to the booking back and invoicing in the customers presence, so the invoice is only received a few days later, after I had to call the call centre, since the internet download as per sms instruction did not work for whatever stupid reason. Now it appears I was still charged for 4 days and not 3, since according to the assistant in the call centre, if one pre-books for 4 days you have to pay for 4 days. In that case, I put it to you that your staff arent properly trained and misrepresent the terms and conditions to the clients. Train your people properly and get back to me about disounting me the extra day of rental. I am a return customer and will never pre-pay again if this..