If you cancel a ride, you'll get an in-app message letting you know if the ride qualifies for a refund of the usual cancellation fee. You'll only get this refund if you rebook the ride within 15 minutes and complete the trip.
Flexible cancellations are only available to Gold, Platinum and Diamond members. Pool and Express Pool trips are not eligible. This benefit can be used once per hour at most, up to three total uses per earnings window. This benefit is only available in the US and may not be available in all locations, such as certain airports and venues/stadiums.