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Merchants can now generate GTBank reserved accounts, by simply passing “058” as one of the bank codes in the preferredBanks request parameter.
Webhook notifications for Rejected Payments
Merchants should now be able to get webhook notifications sent to their transaction completion endpoint once a payment is rejected, so that they can perform desired action for such transactions like closing the transaction and informing the user why his payment was not successfully processed.
Sample payload for rejected payment is outline here:Webhook Events and Request Structure