save and load using sharedObject in AS3 - actionscript-3

Question

i am currently doing an experiment to save each name of the user(not replacing it every time we save the new one).
my problem is the getLocal() function.I defined a variable with the type of string to make the SharedObject store the data to local storage with the name of the variable i defined which it is the name of the each user.
but i get this error:
Error #2134: Cannot create SharedObject. at
flash.net::SharedObject$/getLocal() at classes::Main/saveNewUser()
at classes::Main/promtSave()
here is my code
package classes {
import flash.display.MovieClip;
import flash.net.SharedObject;
import flash.text.TextField;
import classes.user.User;
public class Main extends MovieClip {
private var _user:User;
private var _properties:Object;
private var validOrNot_txt:TextField;
private var _name_input_txt:TextField;
//define a shared object to store our user data
private var database:SharedObject;
//define an array that will hold all users
private var userList:Array;
private var nameEntered:String;
public function Main() {
userList = [];
_name_input_txt = Name_input;
validOrNot_txt = valid_or_not_TXT;
validOrNot_txt.autoSize = 'center';
//_properties={Name:String,age:int,gender:String};
// constructor code
}
public function get user():User{
return _user;
}
private function saveNewUser():void{
nameEntered=_name_input_txt.text;
_user = new User();
_user._Name = _name_input_txt.text;
database = SharedObject.getLocal(nameEntered);
userList.push(_user);
database.data.Name = _user._Name;
}
}
}
here's the code in the timeline
import flash.events.MouseEvent;
login_btn.addEventListener(MouseEvent.CLICK, promtSave);
login_btn.buttonMode=true;
trace(Name_input.length);
function promtSave(e:MouseEvent):void{
if(Name_input.length>1){
saveNewUser();
}else{
throw(new Error('you did not enter anything'));
}
}
anybody, please help me with this :'(