There can be several reasons why it shows in Messenger that you have unread messages but you can't find them. Here are some possible explanations:

1. Hidden or Filtered Message Requests: It's possible that the message you're looking for is in a hidden or filtered message request folder. Messenger has a feature that filters messages from people who are not your confirmed friends into a separate folder. To check for hidden or filtered messages, follow these steps [1]:

   • Open the Messenger app on your device.
   • Tap on the three horizontal lines in the top left corner.
   • Tap on "Message Requests."
   • Look for the "Filtered" tab. Messages from people who are not your confirmed friends may be located here.

2. Technical Glitch: Sometimes, Messenger may display an incorrect unread message count due to a technical glitch. This can happen if the app fails to update the message status properly. In such cases, logging out and back into the Messenger app, clearing the cache, or updating the app may resolve the issue [2].

3. Deleted Messages: If you received a message and it was deleted before you had a chance to read it, Messenger may still show it as an unread message. This can happen if the sender deletes the message or if it was automatically deleted by Messenger due to certain conditions [2].

4. Message Reactions: Messenger also considers message reactions as notifications, which can appear as unread messages. If someone reacts to a message you sent, it may show up as an unread message notification [2].

Learn more:

1. Why does it show in Messenger that I have unread messages ...
2. [Fixed] Facebook messenger shows an "unread message" icon but no message
3. [UPDATED 2023] How Do I Clear or Hide The Facebook Messenger Notification When I Don't Have A New Message? - SocMedSean - Social Media Sean