Now you need to direct the customer to the payment iframe (redirect_url/iframe_url). The customer sees something like this:
In case of direct debit he needs to enter his bank details, and confirm the SEPA direct debit mandate. Our system authorises the transaction, and captures the payment. (It is also possible to capture later. This is explained in the Reference part.) If we had created a transaction for credit card payment, the customer would need to enter the card details.
When the payment was successful, the customer is directed back to the URL you had passed to redirect_url/url_success. If the customer quits the process, or the payment cannot be authenticated, he is returned to redirect_url/url_failure.