Hey C_E_4,
Make sure Facebook Messenger is up-to-date on both the Apple Watch and the iPhone. If issue continues, delete the app on your Apple Watch and then re-install it.
How to manually update apps on your Apple device:
"How to manually update apps on your Apple Watch
- Open the App Store and scroll down to the bottom.
- Tap Account.
- Tap Updates.
- Tap Update next to an app to update only that app, or tap Update All."
If you need to reinstall the app, start with the guidance in these links to Delete apps from your Apple Watch and Download apps on your Apple Watch.
If you're unable to resolve the issue and it only occurs with the Facebook Messenger app, reach out to FaceBook's app developer. They are the experts that will be ablate further assist.
For information on how to contact an app developer, click here: How to contact an app developer.
Take care.