flask-login login_required装饰器页面不跳转

Question

装饰函数

@app.route('/add', methods=['POST'])
@login_required
def add():
    todo = request.get_json()['todo']
    todo_document = {
 'content': todo,
 'status': 0,
 'date': datetime.now()
    }
 db.create(todo_document)
    return 'added'

跳转页面

login_manager.login_view = 'login'

登录视图

@app.route('/login', methods=['GET', 'POST'])
def login():
    login_form = LoginForm()
    if login_form.validate_on_submit():
        username = login_form.username.data
        password = login_form.password.data
        user = User.objects(username=username).first()
        if user is not None and check_password_hash(user.password, password):
            login_user(user)
            next = request.args.get('next')
            if next is None or not next.startswith('/'):
                next = url_for('index3')
            return redirect(next)
        flash('用户名或密码错误！')
    return render_template('login.html', form=login_form)

F12查看请求，发现add已经跳转到login，login视图响应内容也是login.html，但是页面却没有跳转到login.html。求指导额！