diff --git a/ntfy/bot.py b/ntfy/bot.py
index c5681ea..2414e99 100644
--- a/ntfy/bot.py
+++ b/ntfy/bot.py
@@ -160,7 +160,9 @@ class NtfyBot(Plugin):
                 line = line.decode("utf-8").strip()
                 self.log.trace("Received notification: %s", line)
                 message = json.loads(line)
-                if message["event"] != "message":
+                if not "event" in message or message["event"] != "message":
+                    if "error" in message:
+                        await self.handle_subscription_error(message, topic, self.tasks[topic.id])
                     continue
                 self.log.debug("Received message event: %s", line)
                 # persist the received message id
@@ -186,6 +188,27 @@ class NtfyBot(Plugin):
                         self.log.exception(
                             "Failed to send matrix message!", exc_info=exc)
 
+    async def handle_subscription_error(self, message: dict, topic: Topic,
+                                        task: asyncio.Task) -> None:
+        self.log.error(message["error"])
+        code = message["code"] if "code" in message else None
+        match code:
+            case 42909:
+                if task.cancel():
+                    for sub in await self.db.get_subscriptions(topic.id):
+                        html_content = "<span>Authentication failed, please check the access token. Subscription has been cancelled.</span>"
+                        text_content = await parse_html(html_content.strip())
+                        content = TextMessageEventContent(
+                            msgtype=MessageType.TEXT,
+                            format=Format.HTML,
+                            formatted_body=html_content,
+                            body=text_content,
+                        )
+                        await self.client.send_message(sub.room_id, content)
+                else:
+                    self.log.error("Failed to cancel subscription task")
+
+
     def build_message_content(self, server: str, message) -> str:
         topic = message["topic"]
         body = message["message"]