Edit a sent message
You can edit a message after you’ve sent it. Your modifications are immediately applied to your correspondents.
iOS 
- Tap the message to display its options.
- Tap Edit
.
- Edit the text.
- Tap Send to send your corrected text.
Android 
- Press the message to display its options.
- Tap
Edit.
- Edit the text.
- Tap Update to send your corrected text.