No support for issue with prebooking

I prebooked an Uber ride 1 day in advance for a pickup on Monday morning at 8:00 am. I received a message at 7:00 am on Monday that the driver will pick me up at 8:00 am. At 7:55 am I got a message stating that the driver is delayed and will only pick me up at 8:40. He was still 17 kms far away from my place at that time. Since I had to get to work, I cancelled the trip and booked a new one, which cost ZAR 70 more than the prebooked trip. I have been trying to chat to Uber Help on their website, but they are just giving me standardised, automated answers and not helping at all. There is no phone number for Customers to call. I request a refund of the ZAR 70 I had to pay more, because the prebooking was delayed. What is the point in prebooking, if the driver is 40 minutes delayed.