Updating/removing a credit card in the iOS app Currently you can only replace an existing saved credit or debit card with another. However, after four unsuccessful attempts to enter your 4-digit pin, existing saved credit card details will be removed from the app. Follow the steps below to update your credit/debit card details. Step 1. Open the scan icon and scan your Snapper card Step 2. Select the top-up amount on the dial and then confirm top-up Step 3. On the payment detail screen, tap on Replace card (next to the credit card details). This will direct you to a new screen to enter the new credit/debit card details. Step 4. Update bank card details and tap on Replace card at the bottom of the screen. Step 5. Create a new 4-digit pin and then re–confirm.