I'm trying to make callout using  "Continuation" but the endpoint doesn't receive the request
            and I get the request like  "Continuation-3".and I didn't get the response as well.

            please check it once

            Class :::
            ---------

               public Object startRequest(String username,String password,String url,String accesstoken,String eventid) {

                   HttpRequest req = new HttpRequest();
                   System.debug('UserName:::'+username+ ':' + 'Password::::' + password+ ':' + 'URL::::' +url+ ':' + 'AccessToken:::' +accesstoken+ ':' + 'EventId:::' +eventid);
                   String url1 = 'https://xxxxxxxxx/api/xml?action=report-event-participants-complete-information&account-id=1319228412&session=apac1breezivz5ryh7ggboqkse&sco-id=1310582568';

                   req.setMethod('GET');
                   req.setEndpoint(url1);
                   Continuation con = new Continuation(60);
                   con.state = con.addHttpRequest(req);
                   con.continuationMethod = 'processResponse';
                   requestLabel = con.addHttpRequest(req);
                   this.requestLabel = con.addHttpRequest(req);
                   System.debug('Request:::===='+requestLabel); // This line prints : Request:::====Continuation-3
                   return con;
            }

                public Object processResponse() {
                    HttpResponse res = Continuation.getResponse(this.requestLabel);
                    this.result = res.getBody();
                    System.debug('Response:::'+result);
                    if(res.getBody() != null && res.getStatusCode() == 200)
                         XMLparserUpdate s = new XMLparserUpdate(res.getBody(),eventid,EventName);
                    return null;
               }

               Thanks