inconvenience when consuming WebService SOAP from C #

I want to consume this WS SOAP, I select the method "AuthenticaInicioOperacion" it asks me for 3 input data and only returns the name of the method, nothing more.

$url = "http://sptc.mtc.gob.pe/qacitv/WSInterOperabilidadCITV.svc?wsdl";
    try {
    $para=Array('CODENTIDA'=>'12345678','CODLOCAL'=>'12345678','CODIV'=>'8W9J#%KBNG1asdvesqwgh');
       $client = new SoapClient($url,array("trace" => 1));
       $result=$client->autentificaInicioOperacion($para);
      print_r($Result);
   } catch ( SoapFault $e ) {
       echo $e->getMessage();
   }

What I find strange is that when I try this WS in an app I enter the method and in the input arguments it shows me a sub method I do not know very well about this.

Help ... or explain a little, I'm using PHP 7