The Plutus Cards don't need to be topped up, their balances are unified with the Plutus Account as regular debit cards.
Plutus Card balance
Following our partner transition, the Plutus Account and Plutus Card now share a unified balance. This integration means there's no longer a need to top up your Plutus Account and Plutus Card separately. Simply depositing funds into your account balance makes them immediately available for spending with any of your Plutus Cards.
Can I top up my account balance in ways other than fiat deposits?
Currently, the only method to add balance to your account is through fiat deposits. We do not offer alternative methods for account top-ups at this time.