diff --git a/.gitignore b/.gitignore
index e9a76db..dc46fad 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,4 +5,4 @@ LineBotPy.code-workspace
 .env
 creds.json
 .DS_Store
-virtEnv/*
\ No newline at end of file
+venv/*
\ No newline at end of file
diff --git a/app.py b/app.py
index bb968aa..d35e641 100644
--- a/app.py
+++ b/app.py
@@ -5,12 +5,22 @@
 
 from flask import Flask, request, abort
 
-from linebot import LineBotApi, WebhookHandler
-from linebot.exceptions import InvalidSignatureError
-from linebot.models import (
+from linebot.v3 import (
+    WebhookHandler
+)
+from linebot.v3.exceptions import (
+    InvalidSignatureError
+)
+from linebot.v3.messaging import (
+    Configuration,
+    ApiClient,
+    MessagingApi,
+    ReplyMessageRequest,
+    TextMessage
+)
+from linebot.v3.webhooks import (
     MessageEvent,
-    TextMessage,
-    TextSendMessage,
+    TextMessageContent
 )
 
 #### bot code ####
@@ -30,7 +40,7 @@
     print("Specify LINE_CHANNEL_ACCESS_TOKEN as environment variable.")
     sys.exit(1)
 
-line_bot_api = LineBotApi(channel_access_token)
+configuration = Configuration(access_token=channel_access_token)
 handler = WebhookHandler(channel_secret)
 
 
@@ -56,23 +66,27 @@ def callback():
 
 
 # Handle text messages
-@handler.add(MessageEvent, message=TextMessage)
+@handler.add(MessageEvent, message=TextMessageContent)
 def handle_message(event):
     # user_line_id = event.source.user_id
     chat_msg = event.message.text
-
     # handle all normal bot commands
     response = bot.handle_cmd(chat_msg)
-    send_response(response, event.reply_token)
 
-
-def send_response(response, reply_token):
-    if response != "":
-        line_bot_api.reply_message(reply_token, TextSendMessage(text=response))
+    if response == "":
         return
 
+    with ApiClient(configuration) as api_client:
+        line_bot_api = MessagingApi(api_client)
+        line_bot_api.reply_message_with_http_info(
+            ReplyMessageRequest(
+                reply_token=event.reply_token,
+                messages=[TextMessage(text=response)]
+             )
+        )
+
 
 if __name__ == "__main__":
-    port = int(os.environ.get("PORT", 5000))
+    port = int(os.environ.get("PORT", 8000))
     app.run(host="0.0.0.0", port=port)
 
diff --git a/requirements.in b/requirements.in
new file mode 100644
index 0000000..4e4ce8b
--- /dev/null
+++ b/requirements.in
@@ -0,0 +1,6 @@
+flask
+requests
+gunicorn
+line-bot-sdk
+pytz
+python-dotenv
\ No newline at end of file
diff --git a/requirements.txt b/requirements.txt
index 0c81fbd..cbaec93 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,25 +1,86 @@
-aiohttp==3.8.3
-aiosignal==1.2.0
-async-timeout==4.0.2
-attrs==22.1.0
-certifi==2022.9.24
-charset-normalizer==2.1.1
-click==8.1.3
-Flask==2.2.2
-frozenlist==1.3.1
-future==0.18.2
-gunicorn==20.1.0
-idna==3.4
-importlib-metadata==5.0.0
-itsdangerous==2.1.2
-Jinja2==3.1.2
-line-bot-sdk==2.3.0
-MarkupSafe==2.1.1
-multidict==6.0.2
-python-dotenv==0.21.0
-pytz==2022.5
-requests==2.28.1
-urllib3==1.26.12
-Werkzeug==2.2.2
-yarl==1.8.1
-zipp==3.10.0
+#
+# This file is autogenerated by pip-compile with Python 3.12
+# by the following command:
+#
+#    pip-compile
+#
+aenum==3.1.15
+    # via line-bot-sdk
+aiohttp==3.9.5
+    # via line-bot-sdk
+aiosignal==1.3.1
+    # via aiohttp
+annotated-types==0.7.0
+    # via pydantic
+attrs==23.2.0
+    # via aiohttp
+blinker==1.8.2
+    # via flask
+certifi==2024.6.2
+    # via requests
+charset-normalizer==3.3.2
+    # via requests
+click==8.1.7
+    # via flask
+deprecated==1.2.14
+    # via line-bot-sdk
+flask==3.0.3
+    # via -r requirements.in
+frozenlist==1.4.1
+    # via
+    #   aiohttp
+    #   aiosignal
+future==1.0.0
+    # via line-bot-sdk
+gunicorn==22.0.0
+    # via -r requirements.in
+idna==3.7
+    # via
+    #   requests
+    #   yarl
+itsdangerous==2.2.0
+    # via flask
+jinja2==3.1.4
+    # via flask
+line-bot-sdk==3.11.0
+    # via -r requirements.in
+markupsafe==2.1.5
+    # via
+    #   jinja2
+    #   werkzeug
+multidict==6.0.5
+    # via
+    #   aiohttp
+    #   yarl
+packaging==24.1
+    # via gunicorn
+pydantic==2.7.4
+    # via line-bot-sdk
+pydantic-core==2.18.4
+    # via pydantic
+python-dateutil==2.9.0.post0
+    # via line-bot-sdk
+python-dotenv==1.0.1
+    # via -r requirements.in
+pytz==2024.1
+    # via -r requirements.in
+requests==2.31.0
+    # via
+    #   -r requirements.in
+    #   line-bot-sdk
+six==1.16.0
+    # via python-dateutil
+typing-extensions==4.12.2
+    # via
+    #   pydantic
+    #   pydantic-core
+urllib3==2.2.2
+    # via
+    #   line-bot-sdk
+    #   requests
+werkzeug==3.0.3
+    # via flask
+wrapt==1.16.0
+    # via deprecated
+yarl==1.9.4
+    # via aiohttp
diff --git a/runtime.txt b/runtime.txt
index b5f092a..7f3d94a 100644
--- a/runtime.txt
+++ b/runtime.txt
@@ -1 +1 @@
-python-3.9.15
\ No newline at end of file
+python-3.12.4
\ No newline at end of file