为什么要在沙盒PayPal "User is not allowed to perform this action"

Question

我将以下消息发布到https://svcs.sandbox.paypal.com/AdaptivePayments/Pay:

<?xml version="1.0" encoding="utf-16"?>
<PayRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
            xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <requestEnvelope>
        <detailLevel>ReturnAll</detailLevel>
        <errorLanguage>en_US</errorLanguage>
    </requestEnvelope>
    <clientDetails>
        <ipAddress>127.0.0.1</ipAddress>
        <deviceId>platformSDKDotNetSample</deviceId>
        <applicationId>APP-80W284485P519543T</applicationId>
        <customerType>Developer</customerType>
        <partnerName>GreenDot</partnerName>
        <customerId>GreenDot</customerId>
    </clientDetails>
    <actionType>PAY</actionType>
    <cancelUrl></cancelUrl>
    <currencyCode>USD</currencyCode>
    <memo>MP ref 8050042402450937112</memo>
    <receiverList>
        <receiver>
            <amount>5</amount>
            <email>[e-mail]</email>
            <primary>false</primary>
            <invoiceId>123456</invoiceId>
            <paymentType>PERSONAL</paymentType>
        </receiver>
    </receiverList>
    <senderEmail>[e-mail]</senderEmail>
    <returnUrl></returnUrl>
    <trackingId>111111</trackingId>
    <fundingConstraint>
        <allowedFundingType>
            <fundingTypeInfo>
                <fundingType>RECEIVABLE</fundingType>
            </fundingTypeInfo>
        </allowedFundingType>
    </fundingConstraint>
</PayRequest>

和得到这个响应:

<ns3:FaultMessage xmlns:ns3="http://svcs.paypal.com/types/common" 
                  xmlns:ns2="http://svcs.paypal.com/types/ap">
    <responseEnvelope>
        <timestamp>2013-04-02T14:25:32.304-07:00</timestamp>
        <ack>Failure</ack>
        <correlationId>54974e7a32854</correlationId>
        <build>5563463</build>
    </responseEnvelope>
    <error>
        <errorId>550001</errorId>
        <domain>PLATFORM</domain>
        <subdomain>Application</subdomain>
        <severity>Error</severity>
        <category>Application</category>
        <message>User is not allowed to perform this action</message>
        <parameter>Sender is not allowed to perform this action</parameter>
    </error>
</ns3:FaultMessage>

发件人邮箱是我设置的个人账号。经过验证，余额为5000美元。卡状态为"已激活"。为什么我得到"用户不允许执行此操作"?

Answer 1

在API文档中找到此信息

注意:FundingConstraint对标准API调用者不可用许可的水平;有关更多信息，请参阅Adaptive部分付款权限级别。

如果我从请求中删除fundingConstraint节点，我将得到一个成功的响应。

是否有可能在沙箱中测试需要更高权限级别的请求?