$client = new nusoap_client('http://www.xx.com/Site_Service.svc?wsdl');
    $client->soap_defencoding = 'UTF-8';
    $client->decode_utf8 = false;
    $isGPara = array("site" => "site.zz", "groupID" => 'ieuur8383');
    $isGResult = $client->call('Check_Site', $isGPara);
   
    it shows :
    HTTP/1.1 415 Cannot process the message because the content type 'text/xml; charset=UTF-8' was not the expected type 'application/soap+msbin1'

any help appreciate :)