If your top-up transaction was unsuccessful, consider the following common issues:

1. Card Details: Ensure that the card details you entered are correct.
2. Sufficient Funds: Verify that your card has enough funds to complete the transaction.
3. Transaction Limits: Check if your daily transaction limit has been exceeded.
4. Card Ownership: You can only top up using a card that is registered in your name.

Review these factors and try the transaction again.