PayPal Express并行付款-未显示购物车

Question

我的整合有点问题。我将PayPal Express与并行付款一起使用。如果我使用以下代码（$ params通过curl发送-SetExpressCheckout）：

$params = array(
'RETURNURL' => $rootURL . "return.php",
'CANCELURL' => $rootURL . "cancel.php",
'NOSHIPPING' => '1',
'BRANDNAME' => 'My Shop',   
'PAYMENTREQUEST_0_AMT' => '1.37',
'PAYMENTREQUEST_0_CURRENCYCODE' => 'EUR',
'PAYMENTREQUEST_0_ITEMAMT' => '1.37',
'PAYMENTREQUEST_0_SELLERPAYPALACCOUNTID' => 'email_1@domain.com',
'PAYMENTREQUEST_0_PAYMENTREQUESTID' => 'GHTFVGFUOLG',
'PAYMENTREQUEST_0_PAYMENTACTION' => 'Sale',
'L_PAYMENTREQUEST_0_NAME0' => 'Test Item 1',
'L_PAYMENTREQUEST_0_QTY0' => '1',
'L_PAYMENTREQUEST_0_AMT0' => '1.37'
);

工作正常-我看到这样的购物车列表 https://imgur.com/a/OuAWuMb

但是如果我正在使用包含第二个接收器的这段代码：

$params = array(
'RETURNURL' => $rootURL . "return.php",
'CANCELURL' => $rootURL . "cancel.php",
'NOSHIPPING' => '1',
'BRANDNAME' => 'My Shop',   
'PAYMENTREQUEST_0_AMT' => '1.00',
'PAYMENTREQUEST_0_CURRENCYCODE' => 'EUR',
'PAYMENTREQUEST_0_ITEMAMT' => '1.00',
'PAYMENTREQUEST_0_SELLERPAYPALACCOUNTID' => 'email_1@domain.com',
'PAYMENTREQUEST_0_PAYMENTREQUESTID' => 'GHTFVGFUOLG',
'PAYMENTREQUEST_0_PAYMENTACTION' => 'Sale',
'L_PAYMENTREQUEST_0_NAME0' => 'Test Item 1',
'L_PAYMENTREQUEST_0_QTY0' => '1',
'L_PAYMENTREQUEST_0_AMT0' => '1.00',
'PAYMENTREQUEST_1_AMT' => '3.00',
'PAYMENTREQUEST_1_CURRENCYCODE' => 'EUR',
'PAYMENTREQUEST_1_ITEMAMT' => '3.00',
'PAYMENTREQUEST_1_SELLERPAYPALACCOUNTID' => 'email_2@domain.com',
'PAYMENTREQUEST_1_PAYMENTREQUESTID' => 'HFTZIGDTUGFD',
'PAYMENTREQUEST_1_PAYMENTACTION' => 'Sale',
'L_PAYMENTREQUEST_1_NAME0' => 'Test Item 2',
'L_PAYMENTREQUEST_1_QTY0' => '1',
'L_PAYMENTREQUEST_1_AMT0' => '3.00'
);

未显示购物车-仅显示金额。参见https://imgur.com/a/g1eBfXD

这是怎么了？