If you have lost your card, you should open the Countingup app and immediately freeze your card to prevent anyone from using it. (How do I freeze my card?)
If you find your card again, you can simply unfreeze it and use it as normal.
If you need a new card, follow these steps:
- Open the Countingup app
- Go to the 'Card' tab
- Tap 'Cancel'
- Tap 'Lost' when prompted for the reason
- Tap 'Cancel & reissue' to get a new card sent to you, or just 'Cancel' if you don't want a new card