There is a issue with one of your power supplies.
If you received your Cel-Fi Duo from your cellular provider please reach out to their customer support.
If you purchased your Cel-Fi Duo directly from Cel-Fi.com contact us, please note in the comments that you are having an issue with the power supply and we will send you a replacement asap.
**Network Unit (NU) is also known as the Window Unit (WU).**