If you requested a ride with card payment and the payment method wasn't changed, the money will be debited automatically. You don't need to give the driver cash.
If you accidentally pay both in cash and by card, try calling the driver within 24 hours using the button in your ride history.
Sometimes your bank might notify you of two separate charges because first the funds are frozen on your card, then debited later. Check your bank statement to make sure there weren't any extra charges.
If you have any other payment questions, let us know! We'll be happy to help.