diff --git a/backend/community/views.py b/backend/community/views.py
index aea131f..17d4f7b 100644
--- a/backend/community/views.py
+++ b/backend/community/views.py
@@ -38,14 +38,19 @@ class ActivityViewSet(viewsets.ReadOnlyModelViewSet):
         
         activity = self.get_object()
         
-        # Check if already signed up (and not cancelled)
-        existing_signup = ActivitySignup.objects.filter(activity=activity, user=user).exclude(status='cancelled').first()
-        if existing_signup:
+        # 1. Check confirmed signup
+        if ActivitySignup.objects.filter(activity=activity, user=user, status='confirmed').exists():
             return Response({'error': '您已报名该活动'}, status=400)
+            
+        # 2. Get pending signup (for retry)
+        pending_signup = ActivitySignup.objects.filter(activity=activity, user=user, status='pending').first()
         
-        # Check limit (exclude cancelled)
-        current_count = activity.signups.exclude(status='cancelled').count()
-        if current_count >= activity.max_participants:
+        # 3. Check limit (exclude cancelled, exclude current pending)
+        query = activity.signups.exclude(status='cancelled')
+        if pending_signup:
+             query = query.exclude(id=pending_signup.id)
+             
+        if query.count() >= activity.max_participants:
              return Response({'error': '活动名额已满'}, status=400)
         
         # Get signup info
@@ -77,32 +82,43 @@ class ActivityViewSet(viewsets.ReadOnlyModelViewSet):
             import time
             from wechatpayv3 import WeChatPayType
             
-            # Create Order
-            # Check if there is a pending order
-            pending_order = Order.objects.filter(
-                wechat_user=user, 
-                activity=activity, 
-                status='pending'
-            ).first()
+            # Create or Get Order
+            order = None
+            if pending_signup and pending_signup.order:
+                # Reuse existing order if it's pending
+                if pending_signup.order.status == 'pending':
+                    order = pending_signup.order
+                    # Update contact info if needed
+                    contact_name = signup_info.get('name') or signup_info.get('participant_name') or user.nickname or 'Activity User'
+                    contact_phone = signup_info.get('phone') or user.phone_number or ''
+                    if contact_name: order.customer_name = contact_name
+                    if contact_phone: order.phone_number = contact_phone
+                    order.save()
             
-            if pending_order:
-                order = pending_order
-                # Update info if needed? Maybe not.
-            else:
-                # 优先从报名信息获取联系方式
-                contact_name = signup_info.get('name') or signup_info.get('participant_name') or user.nickname or 'Activity User'
-                contact_phone = signup_info.get('phone') or user.phone_number or ''
+            if not order:
+                # Check independent pending order
+                pending_order = Order.objects.filter(
+                    wechat_user=user, 
+                    activity=activity, 
+                    status='pending'
+                ).first()
                 
-                order = Order.objects.create(
-                    wechat_user=user,
-                    activity=activity,
-                    total_price=activity.price,
-                    status='pending',
-                    quantity=1,
-                    customer_name=contact_name,
-                    phone_number=contact_phone,
-                    shipping_address=activity.location or '线下活动', # 使用活动地点作为发货地址
-                )
+                if pending_order:
+                    order = pending_order
+                else:
+                    contact_name = signup_info.get('name') or signup_info.get('participant_name') or user.nickname or 'Activity User'
+                    contact_phone = signup_info.get('phone') or user.phone_number or ''
+                    
+                    order = Order.objects.create(
+                        wechat_user=user,
+                        activity=activity,
+                        total_price=activity.price,
+                        status='pending',
+                        quantity=1,
+                        customer_name=contact_name,
+                        phone_number=contact_phone,
+                        shipping_address=activity.location or '线下活动',
+                    )
 
             # Generate Pay Code
             out_trade_no = f"ACT{activity.id}U{user.id}T{int(time.time())}"
@@ -128,14 +144,18 @@ class ActivityViewSet(viewsets.ReadOnlyModelViewSet):
             if code in range(200, 300):
                 code_url = result.get('code_url')
                 
-                # Create a pending signup record so we can update it later
-                ActivitySignup.objects.create(
-                    activity=activity, 
-                    user=user,
-                    signup_info=signup_info,
-                    status='pending',
-                    order=order
-                )
+                if pending_signup:
+                    pending_signup.signup_info = signup_info
+                    pending_signup.order = order
+                    pending_signup.save()
+                else:
+                    ActivitySignup.objects.create(
+                        activity=activity, 
+                        user=user,
+                        signup_info=signup_info,
+                        status='pending',
+                        order=order
+                    )
                 
                 return Response({
                     'payment_required': True,
diff --git a/frontend/src/pages/activity/Detail.jsx b/frontend/src/pages/activity/Detail.jsx
index 3493fdf..495c888 100644
--- a/frontend/src/pages/activity/Detail.jsx
+++ b/frontend/src/pages/activity/Detail.jsx
@@ -3,7 +3,7 @@ import React, { useState, useEffect } from 'react';
 import { useParams, useNavigate } from 'react-router-dom';
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import { motion, useScroll, useTransform } from 'framer-motion';
-import { ArrowLeftOutlined, ShareAltOutlined, CalendarOutlined, ClockCircleOutlined, EnvironmentOutlined, UserOutlined, UploadOutlined } from '@ant-design/icons';
+import { ArrowLeftOutlined, ShareAltOutlined, CalendarOutlined, ClockCircleOutlined, EnvironmentOutlined, UserOutlined, UploadOutlined, PayCircleOutlined } from '@ant-design/icons';
 import confetti from 'canvas-confetti';
 import { message, Spin, Button, Result, Modal, Form, Input, Select, Radio, Checkbox, Upload } from 'antd';
 import { getActivityDetail, signUpActivity, queryOrderStatus } from '../../api';
@@ -316,6 +316,10 @@ const ActivityDetail = () => {
                <UserOutlined />
                <span>{activity.current_signups || 0} / {activity.max_participants} 已报名</span>
              </div>
+             <div style={{ display: 'flex', alignItems: 'center', gap: 8 }}>
+               <PayCircleOutlined />
+               <span>{activity.is_paid ? `¥${activity.price}` : '免费'}</span>
+             </div>
           </div>
           
           <div style={{ display: 'flex', gap: 10 }}>