Payment Processing Using PaymentExpress GateWay in iphone

[manga]

Hai,

When i accessing PaymentExpress GateWay webservices.
I get following response
<Txn>
<Transaction success="0" reco="U5" responseText="Declined" pxTxn="True">
<Authorized>0</Authorized>
<Reco>U5</Reco>
---
---
---
</Txn> like that.



When i send response Body as follows


@"<Txn>\n"
"<PostUsername>TestUsername</PostUsername>\n"
"<PostPassword>Testpassword</PostPassword>\n"
"<CardHolderName>%@</CardHolderName>\n"
"<CardNumber>%@</CardNumber>\n"
"<Amount>%@</Amount>\n"
"<DateExpiry>%@</DateExpiry>\n"
"<Cvc2>1234</Cvc2>\n"
"<Cvc2Presence>1</Cvc2Presence>\n"
"<InputCurrency>USD</InputCurrency>\n"
"<TxnType>Purchase</TxnType>\n"
"<TxnId>0001</TxnId>\n"
//"<TxnRef>00025a</TxnRef>\n"
// "<EnableDuplicateCheck>0</EnableDuplicateCheck>\n"
//"<EnableRm>0</EnableRm>\n"
"<MerchantReference>Test Transaction</MerchantReference>\n"
"</Txn>\n




Can you please tell me ,Why it happens?
Its Very Urgent.....Please....





Thanks...