Recently uber have started putting a hold on my card before my trip and sometimes they put 2 charges on my card if the trip amount changes. The holds can take between 1 to 31 days to return to your account and it's really stressful when you need the cash back. They only used to charge you after the ride, I see why they do this (to prevent fraud and accounts being credited) but it's just a pain for people that rely on uber. Recently it has also failed to find drivers and has to cancel the rides.