Aramex速率计算器APT返回错误代码“；ISE01”；

Aramex Rate计算器API返回错误代码ISE01和以下错误消息：

请求时获取计算速率时发生内部服务器错误

这个错误的原因是什么？

以下是Aramex费率计算器API的示例代码：

<?php
$params = array(
    'ClientInfo'            => array(
                                'AccountCountryCode'    => 'JO',
                                'AccountEntity'         => 'AMM',
                                'AccountNumber'         => '00000',
                                'AccountPin'            => '000000',
                                'UserName'              => 'user@company.com',
                                'Password'              => '000000000',
                                'Version'               => 'v1.0'
                            ),
    'Transaction'           => array(
                                'Reference1'            => '001' 
                            ),
    'OriginAddress'         => array(
                                'City'                  => 'Amman',
                                'CountryCode'               => 'JO'
                            ),
    'DestinationAddress'    => array(
                                'City'                  => 'Dubai',
                                'CountryCode'           => 'AE'
                            ),
    'ShipmentDetails'       => array(
                                'PaymentType'            => 'P',
                                'ProductGroup'           => 'EXP',
                                'ProductType'            => 'PPX',
                                'ActualWeight'           => array('Value' => 5, 'Unit' => 'KG'),
                                'ChargeableWeight'       => array('Value' => 5, 'Unit' => 'KG'),
                                'NumberOfPieces'         => 5
                            )
);
$soapClient = new SoapClient('http://url/to/wsdl.wsdl', array('trace' => 1));
$results = $soapClient->CalculateRate($params); 
echo '<pre>';
print_r($results);
die();
?>