Agent Car Booking Failure

I booked a car through an agent named 'Iya Travel'.The agent has an agreement/special rate with Thrifty, hence I booked via them because it would work out cheaper. Everything was confirmed and I paid a fee of R 250.00 to the agent. They sent an sms confirming my booking (car group, amount, dates and excess) . Upon collection of my vehicle I was told by the car hire company that no voucher was sent by my agent so there is no booking confirmed. I phoned the agent, while trying to explain the situation, I got cut off and the phone was engaged, I could not go through. I had to do a new booking from, at my own capacity: I did not get the car group I initially booked through the agent, the rates were the normal rates, meaning I paid more than what I agreed on with the agent because the agent has a special rate with the car hire company. The excess I paid was more than that was agreed with the agent.<br> I have been phoning the agent and they have been telling me that they are busy looking into the matter and Thrifty will refund me on the extra amount charged. I told the agent that they should refund me the fee of R 250 because they did nothing on my behalf. NO response from them! HELP! <br>