No Refund if car returned early

I booked a rental car through budget on the 25th August for collection on the 26th. It was booked for 12 days. When I collected the vehicle I asked whether I would receive a refund if I returned the vehicle early which the gentleman agreed would happen. I returned the vehicle on the 29th and again asked whether I would get the refund for returning the vehicle early which was again confirmed. Not only did they not closed the rental but I have now been informed that they don't refund for vehicles being returned early. This is absolutely shocking and I would not recommend Budget or Avis to anyone. Having to pay for a service that was not used is absolutely disgusting.