Tap the 3 horizontal stacked lines at the top left corner of the screen.
On the sidebar, you will several options – Your Trips, Wallet, Help, Uber Rewards, Uber Pass, Send a Gift and Settings.
Tap Wallet.
On the Wallet Screen, you will see Uber Cash and below that you will see an option to send a gift and just below Send a gift, you will see Payment Methods.
Under Payment Methods, you will see your existing payment methods which you have added earlier.
When you scroll down, you will see an option to add a new payment method with a + symbol next to it.
Tap Add Payment Method or Redeem Gift Card.
Tap Credit or Debit Card.
On the Add Card screen, Enter your card number, Expiration Date of your card, CVV, Country and Zip Code.
After you enter the required card information, tap Save.