Overview : This feature enables users to define a custom time threshold (e.g., 2 hours), and an alert will be issued immediately once a device has been continuously offline for that custom define duration.
Steps to set off line alert configuration.
1. Navigate to the Setting page :

2. Device Alert : Locate and open the Device Alert Tab(expected to be the last tab)
3. Configure Offline Alert : Open the Offline Alert Tab(expected to be the last sub-tab)