A driver's duty status may appear as Disconnected in the Samsara dashboard if the Samsara Driver App does not have an active internet connection to the cloud. Internet Connectivity States and Best Practices
On the Reports & Driver HOS screen, the driver's status will show as Disconnected in a gray label.
Most of the time this is because the driver has minimized the app and can no longer see it on the screen of the device or because the device does not have an internet connection.
While the app is disconnected, the Samsara Driver App stores data on the device itself, and uploads that information the next time the app is opened or the device regains an internet connection.