The following are preconditions for software such as WhatsApp and Facebook to give message alerts:
1) Make sure that there is a message in the notification bar of the mobile phone. If the notification bar of the mobile phone does not receive a message, go to the system settings to enable WhatsApp and Facebook notifications.
2) If you wish that the watch can give alerts when you've logged on to your facebook, whatapp, etc. on the PC terminal, you need to toggle on "Restore Mobile Phone Notifications" on the mobile terminal Facebook, WhatsApp, etc.
3) The watch needs to be always connected to the mobile phone, and the Bluetooth needs to be always turned on. If the watch still can't receive alerts after you perform the above operations, try to turn the mobile phone Bluetooth on and off once.