The device does not get disenrolled from the DEP or the MDM even if it remains inactive for a long period of time. However, the remote actions and policies that are associated on the device through the portal will be effective on the device only if it is active.
Kindly make sure that the following conditions are satisfied for the device to communicate with the Hexnode portal:
Device is online/does have active internet connectivity
MDM profile needs to be present on the device – in the case of Android: the Hexnode MDM app needs to be present. For iOS, the Hexnode MDM profile needs to be on the device (Settings app > General > Device management)
Once the above conditions are satisfied, kindly try pushing a scan device action from the Hexnode portal from Manage > Devices > Select the device > Actions > Scan device.
If the device is still not communicating with the server, open the Hexnode MDM app > Click on the sync icon towards the top right.
For Android devices, enabling the periodic sync as foreground ensures that synchronization of Android devices with Hexnode servers at all times, even if the battery saver and data saver modes are enabled on the device.