我无法访问wsdl文件中定义的函数。提供了代码和错误代码段

Question

我无法访问wsdl文件中定义的ResloveIP函数。我使用SoapUI检查了服务，它工作正常。请帮忙！

var soap=require('soap');
var url='http://ws.cdyne.com/ip2geo/ip2geo.asmx?wsdl';

soap.createClient(url, function(err, client) {
    if(err){
      console.log(err);
      return;
    }
    //console.log(client.describe());
    client.IP2Geo.IP2GeoSoap.ResolveIP('184.172.104.38');//the ResolveIP function cannot be accessed.
});

错误讯息：