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uppercase(md5(uppercase(md5(SALT) + md5(Х)))), where SALT – secret word; Х – result of string concatenation (with semicolon (;) as delimiter) of the request parameters in order as they located in table from top to bottom excluding DelayPayment, SendNotification, Checkvalue and CustomerNumber, '+' – string concatenation.
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When unique payment token/ID cannot be created the new bill is not created and an error is returned: "Unique payment token/ID cannot be created".
Information about using the 3-D Secure 2.0 protocol when creating a payment.
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