javascript Error: Invalid web service call, missing value for parameter: 'documentId'. code example

Example: javascript Error: Invalid web service call, missing value for parameter: 'documentId'.

/*
Your Javascript must pass parameters named Exactly as in the web service.
Remember that these parameters in client- and server-side are case-sensitive. 
*/

// Web service:
 public static List GetMyObjects(int ObjectId)
    { ...
    
// Javascript:
CallMethodAsync(null, "GetMyObjects", { ObjectId: theCurrentObjId }, function (data) {
                    self.SavedObjects = data.Result;
                    ...
                });