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a) The payment status is returned as "P" (Refund Processed) when the refund request was submitted to the bank using the account information provided by the end customer. Please note that the Refund Processed status doesn't necessarily mean that the customer has received the credit, as the money can later be returned by the recipient's bank if the account information turns out to be incorrect.
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b) The payment status is returned as "J" (Refund rejected) when the money has been returned by the recipient's bank because the account information provided was incorrect. In this case, please ask the customer to confirm that the bank details are correct and that they are the account holder. When you have their correct information you may request the refund again.
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c) To authenticate the legitimacy of the IPN, you may check the parameter secret and/or the parameter signature, which is a HMAC-MD5 hash based on three parameters and a key defined at the PagBrasil Dashboard, menu Account > Settings. The HMAC-MD5 source string is the concatenation of the values of the parameters order, amount_brl and payment_status and the total length for these three parameters. For example, if parameter order="1234567890", amount_brl="39.50" and payment_status="P", the parameter signature would be "3093a7dffa0c04e74e827d1b52ef514e".
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