This article describes what to do if the network is not found.
INSTRUCTIONS & INFO
If the Wi-Fi network cannot be found on a Wi-Fi enabled device, the AT&T Unite Express might be asleep. To wake up, from any screen press the Power key.
Make sure the Mobile Hotspot Wi-Fi network name is set to be broadcast.
Make sure that your connecting device is not blocked.
Turn off your device and take the battery out, wait 10 seconds, put the battery back in, and turn your device on.
Restart your computer.
Turn off or temporarily disable any security programs or firewalls.
If possible, try using another computer or Wi-Fi device to connect to your hotspot. If you can, then the problem is with the device that cannot connect, not the hotspot.