Sent Something Inappropriate

If you sent something inappropriate to someone on facebook messenger and now you want to unsent it then, don’t worry, just follow these steps.

1. Go to your messenger application
2. Now, visit the thread where you want to unsend the message
3. Tap on the message and hold your finger for a few seconds
4. Then, an Unsend option will appear in the middle of the screen
5. Tap on it to unsend the message

Source: https://getassist.net/how-to-see-unsent-messages-on-messenger/