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Once the first card transaction is successful, you get a card token by performing a re-query on the transaction using the Get Transaction Status API, for more info - check this link. When you call this endpoint, you'll obtain a response with a cardDetails object in the request body, which has the cardToken field, which holds the card’s token.
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When a customer selects the card for a new transaction or when you want to charge them subsequently, you make a request to the Charge Card Token endpoint with the saved token and the customer’s email. Ensure you send the same email used for the initial transaction when making this request.
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