If you have not yet done so, then it may help to:
Update your iPhone and Apple Watch to the latest compatible software versions, starting with your iPhone:
- Update the iOS on your iPhone, iPad, or iPod touch - Apple Support
- Update your Apple Watch - Apple Support
Update Messenger to the latest version:
Check that you are following all of the instructions here:
- Use apps on your Apple Watch - Apple Support
- If you can’t download or update apps, or if apps get stuck - Apple Support
- These tips are also helpful for Apple Watch.
Otherwise, for assistance with issues concerning Messenger (a third-party app), I suggest that you consult the developer's support resources and/or contact the developer for assistance.