Regardign GetKeywordPositionEstimate not work in Multiple Keyword Entry request

When I used to pass single Keyword For GetKeywordPostionestimate. then thru Nusoap below request generate.and it's given responce well.

<soap-env:envelope xmlnsoap-env="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlnsoap-enc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:ns6869="http://tempuri.org">
<soap-env:header>
<apiuserauthheader xmlns="http://adcenter.microsoft.com/syncapis">
<username>************</username>
<password>**********</password>
<useraccesskey>****************</useraccesskey>
</apiuserauthheader>
</soap-env:header>
<soap-env:body>
<getkeywordpositionestimate xmlns="http://adcenter.microsoft.com/syncapis">
<apiflags>0</apiflags>
<msndistributionsite>UnitedStates</msndistributionsite>
<currency>USDollar</currency>
<keywordprice>
<adcenterkeywordprice><keyword>bike</keyword>
<exactmatchamt>2</exactmatchamt>
<phrasematchamt>2</phrasematchamt>
<broadmatchamt>2</broadmatchamt>
</adcenterkeywordprice>

</keywordprice>
</getkeywordpositionestimate>
</soap-env:body>
</soap-env:envelope>

But when i used to pass two keyword and nuSoap generate request like

<soap-env:envelope xmlnsoap-env="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlnsoap-enc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:ns6869="http://tempuri.org">
<soap-env:header>
<apiuserauthheader xmlns="http://adcenter.microsoft.com/syncapis">
<username>**************</username>
<password>********</password>
<useraccesskey>************</useraccesskey>
</apiuserauthheader>
</soap-env:header>
<soap-env:body>
<getkeywordpositionestimate xmlns="http://adcenter.microsoft.com/syncapis">
<apiflags>0</apiflags>
<msndistributionsite>UnitedStates</msndistributionsite>
<currency>USDollar</currency>
<keywordprice>
<adcenterkeywordprice><keyword>bike</keyword>
<exactmatchamt>2</exactmatchamt>
<phrasematchamt>2</phrasematchamt>
<broadmatchamt>2</broadmatchamt>
</adcenterkeywordprice>
<adcenterkeywordprice><keyword>home loan</keyword>
<exactmatchamt>3</exactmatchamt>
<phrasematchamt>3</phrasematchamt>
<broadmatchamt>3</broadmatchamt>
</adcenterkeywordprice>
</keywordprice>
</getkeywordpositionestimate>
</soap-env:body>
</soap-env:envelope>

But it's given ErrorBad request.

Can you any one help what' wrong with request?

[3683 byte] By [PratikPatel] at [2008-1-9]