I am setting my session variable to true whenever username and password is correct in my post function.But when I am unable to retrieve my session in my responses function. when I console it, it says undefined.

var session = require('express-session')
var userSchema = new Schema({
  name: String,
  age: Number,
  gender: String,
});
var users = mongoose.model('users', userSchema)
/* GET home page. */
router.post('/login', function(req, res, next) {
var username = req.body.username;
var password = req.body.password;
if(username == "tina" && password == "123456")
{
req.session.login = true;
console.log("session1:" + req.session.login);
setTimeout(function(){ res.redirect("/responses"); }, 3000);
}
else{
res.redirect("/loginerror");
}

});


router.get('/responses', function(req, res, next) {
//if(req.session.login==true){
console.log("session2:" + req.session.login);
users.find({}, function(err,users) {
  if (err) {
  console.log( err);
  throw err;
}
 else{
 console.log("session3:" + req.session.login);
 if(req.session.login){
 console.log("111");
   res.render('responses', { title: 'responses',users:users });
}
 else{
 res.redirect("/loginerror");
}
  }
})
//}


});

router.get('/loginerror', function(req, res, next) {
  res.render('loginerror', { title: 'loginerror' });

});

router.get('/', function(req, res, next) {
  res.render('index', { title: '',users:users });

});

module.exports = router;