HI Ashish,

yaa my issue is resolved ,some days back.Mainly its because of  removing WebMethods value from the URI .

Now am able to send the request,but i am not getting any response in my system.
Actually am trying with salesforce - salesforce integration using Rest Resource. See below one,
Here is my code : Sending Data to Extrnal sys

webService static void callExternalsysAndUpdatereward(string body){
        Http h = new Http();
         HttpRequest req = new HttpRequest();
            req.setEndpoint('xxxxxxxxxxx');
            req.setMethod('POST');
            req.setHeader('Content-Type','application/json');
            req.setBody(body);
            system.debug('Reward Data '+body);   
           // Send the request, and return a response
         HttpResponse res = h.send(req);
         system.debug('HttpResponse res '+res.getbody());
   }

in other system its invoking  properly .Class :

@RestResource(urlmapping='/RewardSearch_and_Send/*')
global class cls_RecieveAndSend_DatatoSrisys
{

    @HttpPost
    global static MyUserDefinedClass doPost()
    {
        RestRequest req = RestContext.request;
        System.debug('req  Body '+req);
        RestResponse res = RestContext.response;
        string strJSON = req.requestBody.toString();
           System.debug('Json O/P is '+strJSON);
        JSONparser parser = JSON.createParser(strJSON);    
    
        Type reqObj = Type.forName('cls_ReceivingSupport');       
        cls_ReceivingSupport rewCls=(cls_ReceivingSupport)parser.readValueAs(reqObj);
     
        MyUserDefinedClass My=new MyUserDefinedClass();
      
        if(rewCls.month==null && rewCls.year!=null && rewCls.empid!=null){
            User u = [select id,name from user where Emp_Id__c=:rewCls.empid];
            System.Debug('Users Name :'+u.Name);
            Reward__c r = [select id,name,Time_Based_Mgmnt__c,Cut_off_Percent__c,Active__c,Rward_Amount__c,User__c from Reward__c where ((User__c=:u.id) AND (CALENDAR_YEAR(Time_Based_Mgmnt__r.Start_Date__c)=:rewCls.year))];
           JSONGenerator gen = JSON.createGenerator(true);
                  gen.writeStartObject();
                  gen.writeStringField('Name',r.Name);
                  gen.writeNumberField('Reward Amount',r.Rward_Amount__c);
                  gen.writeNumberField('Cut-Off',r.Cut_off_Percent__c);
                  gen.writeStringField('Period Data',r.Time_Based_Mgmnt__c);
                  gen.writeStringField('User Data',r.User__c);
                  gen.writeBooleanField('Active',r.Active__c);
                  gen.writeEndObject();
                String jsonString = gen.getAsString();
                System.Debug('Json O/P is '+jsonString);
                My.Data='Rewards List is '+jsonString;
                My.Status='Success';
              
        }
        System.Debug('Json O/P My '+My);
      return My;
    }
  
    global class MyUserDefinedClass {     
        global String Data;      
        //global String Amount;
        global string Status;
    }
}

sending is success to another system,that system is invoking properly but am not able to get the response in first system. can you suggest me on this.