This error indicates there is an issue with the connection to the device itself.
If you are experiencing this when running the Time Attendance sync, try to turn the device unit off and on again.
If this fails, raise a new case online and reference the title of this article confirming the following details:
ID of failed plugin request
public IP address
port number of device
Confirm if your IT whitelisted the following IPs 185.113.242.133 and 185.113.243.133
Grant our team access to your system