Load is not ready please come back tomorrow

I have a truck scheduled to pick up a load then another one for the next dsy. He showed up for the first load and it was cancelled so I sent him on to pick up the second load. He did and delivered it. I told him I would pay 500 for cancelling the first load even thogh we were able to send him on to pick up the next load. He was only out about 4 hours time. He is insisting on full pay of 1300 for the cancelled load. I am going around and around with this guy. I went ahead and paid him but will never use him again.