Hi there!
The possible cause is that the network fails or the device stops running.
You can do as follows to solve it:
1. View the location information about the alarm and confirm the location of the device that generates the alarm.
2. Check whether the device network is normal.
3. Contact the maintenance personnel to check whether the device is started.
4. Contact the maintenance personnel to check the hardware. For example, check whether the network cables are securely connected and whether the switch is working properly.
5. Wait for five minutes and check whether the alarm is cleared in the current alarm list.
For details, please refer to the link here.