Avis van not available after receiving confirmation

Terrible experience, having booked a van 10 days ago online and received a confirmation number(2***-ZA-2 ) only for me to phone to confirm pick up tomorrow, being told van is not available. Imagine if I did not phone to confirm pick up, no one would have even told me it is not available until I arrived at the branch.No joy after speaking to branch and many phone calls. Incurring extra costs due to Avis poor service and being given the run around. Did not expect this from Avis.