DIAGNOSIS The connection between your washer and your home wifi router has dropped. This is common after a router reboot, password change, or if the washer's been unplugged.
FIX 1) On the washer's control panel, press and hold the Wi-Fi button for 3 seconds until it beeps and the icon blinks. 2) Open the LG ThinQ app on your phone. It should guide you through re-pairing. You'll need to select your home network and enter the wifi password again. Make sure your phone is on the same 2.4 GHz network (not 5 GHz).
IF THAT DIDN'T WORK Perform a factory reset on the washer's network settings. Unplug the washer for 1 minute, plug it back in, then immediately press and hold the Temp and Spin buttons together for 5 seconds. Now try the Wi-Fi setup again from scratch.
HEADS UP The washer's wifi module has a fairly short range. If your router is far away or blocked by walls, the connection will be flaky. A wifi extender can help.