In the remote management console you may see some devices with a red flag warning the following: "This device is unable to communicate correctly over SSL (HTTPS), this is normally caused by an incorrect date & time on the device."
In scenarios where a device runs completely flat it's possible that the internal clock has been reset and the device no longer holds the correct date & time. When the device starts up again it fails to update its clock from a time source and will normally have its date set to 1970-01-01. SSL communication requires an accurate date and time to so that security certificates correctly validate.
You will need to manually reset the time on this device so that it can fully communicate as normal, otherwise it will continue to run in this mode and will only report its connection status. Devices with "automatically detect date & time" and a valid connection to a mobile network may be able to reset their time automatically.
Customer support service by UserEcho