Hi,
When your Apple Watch locks or you turn on Do Not Disturb, your notifications go to your iPhone instead of your watch.
- You’ll see
on your watch face when your Apple Watch locks. If your Apple Watch has a passcode, it locks automatically when you aren't wearing it, when it loses contact with your skin, or while it's charging. - If Do Not Disturb is on, you'll see
on your watch face. To turn this feature on or off, swipe up on the watch face, swipe left or right to the Settings glance, then tap
.
Above information also available from this link....
About notifications on your Apple Watch - Apple Support
If nothing above helped, restart your Apple Watch.
- Press and hold the side button until you see the Power Off slider.
- Drag the slider to turn off your device completely.
- After you turn off your Apple Watch, press and hold the side button again until you see the Apple logo.
and your iPhone.
- Press and hold the Sleep/Wake button until the red slider appears.
- Drag the slider to turn your device completely off.
- After the device turns off, press and hold the Sleep/Wake button again until you see the Apple logo.
Then see if Facebook notifications are working.
* message edited by CS