1. You don't have at least 1 euro (or its equivalent in your card's currency) on your balance,
2. You use a different card, not MasterCard or Visa,
3. Problem with the bank - bank blocks the attempts to add the card,
4. Card might not be fit for international transactions,
5. Failed 3-D Secure authentication by your bank,
6. Cardholder name or digits are inserted incorrectly,
7. The same card was previously added in another account,
8. Other reasons.
1. Make sure you have at least 1 euro (or its equivalent) on your balance,
2. Contact the bank and make sure your card is allowed to make international transactions,
3. Try to add the same card via: Mercuryo web wallet, Mercuryo mobile app, Mercuryo widget.