Thanks for reaching out to OkadaBooks. If you live outside Nigeria or Ghana, you can refill your OkadaBooks wallet by logging into your account on the OkadaBooks app (Android). Click profile, click refill. Select Debit/ Credit card. Change NGN to USD.
Follow this link to refill instantly with your card: https://okadabooks.com/payment/card
(Change the NGN on that page to USD)