Django 5.2.4登录认证失败时messages.error消息无法在模板中显示的问题求助

大家好，我最近在用Django 5.2.4做登录功能，碰到个棘手的问题：当用户登录认证失败时，我在login_user视图里用messages.error()设置了错误提示，但重定向回登录页面后，这个消息完全没在模板里显示出来。我已经翻来覆去检查了好多次代码，还是没找到问题所在，把相关的代码都贴出来，麻烦各位帮忙看看哪里出错了？

应用路由配置（loginapp/urls.py） #

from django.urls import path
from django.shortcuts import redirect
from . import views

# urlpatterns of the app checks the function names defined in views
urlpatterns = [
    path('', lambda request: redirect('login', permanent=True)),
    path("login/", views.login_user, name="login"),
]

项目路由配置（项目根目录/urls.py） #

from django.contrib import admin
from django.shortcuts import redirect
from django.urls import path, include

urlpatterns = [
    path("", lambda request: redirect('loginapp/', permanent=True)),
    path('admin/', admin.site.urls),
    path("loginapp/", include("loginapp.urls")),
    path("loginapp/", include('django.contrib.auth.urls')),
]

登录模板（templates/registration/login.html） #

<html lang="en">
<body>
<div class="box">
    {% if messages %}
    <ul class="messages">
        {% for message in messages %}
        <li{% if message.tags %} class="{{ message.tags }}"{% endif %}>{{ message }}</li>
        {% endfor %}
    </ul>
    {% endif %}
    <h2>Welcome to Trevo</h2>
    <h3>Sign in now!</h3>
    <form method="post", action="{% url 'login' %}">
        <!-- Django uses to verify that the form submission is coming from your site and not from a malicious third party. -->
        {% csrf_token %}
        <label for="Username">Username</label><br>
        <input type="text" id="username" name="username"><br>
        <br>
        <label for="Password">Password</label><br>
        <input type="password" id="password" name="password"><br>
        <br>
        <input type="submit" id="submit" name="submit" value="Sign in"><br>
    </form>
</div>
<style>
<!-- 原代码此处未闭合，原样保留 -->
</body>
</html>

视图函数（loginapp/views.py） #

from django.shortcuts import render, redirect
from django.contrib.auth import authenticate, login, logout
from django.contrib import messages
import logging

# Create your views here.
def login_user(request):
    logging.debug(f"Request method: {request.method}")
    if request.method == 'POST':
        username = request.POST['username']
        password = request.POST['password']
        logging.debug(f"POST DATA: {request.POST}")
        user = authenticate(request, username=username, password=password) # built-in contrib.auth
        if user is not None:
            login(request, user)
            logging.debug("Code 0: User authenticated, redirecting to home")
            return redirect('home')
        else:
            messages.error(request, "Invalid username or password. Please try again.")
            logging.debug("Code 1: Invalid credentials, setting error message")
            logging.debug(f"Messages: {list(messages.get_messages(request))}")
            return redirect('login')
    else:
        logging.debug("Code 2: Rendering login page")
        return render(request, "registration/login.html", {})

项目配置（settings.py 相关部分） #

from pathlib import Path

# Build paths inside the project like this: BASE_DIR / 'subdir'.
BASE_DIR = Path(__file__).resolve().parent.parent

# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/5.2/howto/deployment/checklist/

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True
ALLOWED_HOSTS = []

# Application definition
INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'loginapp',
]

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

ROOT_URLCONF = 'loginpage.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [],
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'loginpage.wsgi.application'

MESSAGE_STORAGE = 'django.contrib.messages.storage.session.SessionStorage'
MESSAGE_LEVEL = 10

# Database
# https://docs.djangoproject.com/en/5.2/ref/settings/#databases
DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': BASE_DIR / 'db.sqlite3',
    }
}

# Password validation
# https://docs.djangoproject.com/en/5.2/ref/settings/#auth-password-validators
AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.Minimum'
        # 原代码此处未写完，原样保留
    }
]

另外补充下：我在视图里加了日志，能看到messages.error()确实执行了，日志里也能打印出设置的消息，但就是重定向后模板里的{% if messages %}判断一直是false，完全不渲染消息列表。麻烦各位帮我排查下问题，谢谢啦！

内容来源于stack exchange