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b) The payment status is returned as "J" (Refund rejected) when the refund request was not accepted by the debit card issuing bank. This usually happens when the order is older than 300 days. In this case our system will also send a notification to the e-mail address you registered at the PagBrasil Dashboard, and you may refund the transaction through PagBrasil via bank transfer, by including the following parameters when requesting the refund via API:
customer_bank = Customer's bank number (número do banco). Please find the bank numbers here (column "COD COMPENSAÇÃO").
customer_branch = Branch number (agência).
customer_account = Account number (conta corrente). Must include the hyphen and the verification digit; for example: "12345-6".
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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". In this example, the hash for the signature was computed using the string "123456789039.50P16" with the key "36d5f7184574caf84f5b48530ac0d690".