Diagnosis
Weak 2.4 GHz WiFi signal at the washer's location. Or a network password/encryption type mismatch. The washer's WiFi module is not powerful.
How to Fix It
Move your router closer or use a WiFi extender on the 2.4 GHz band. During setup, hold your phone right next to the washer's control panel. Ensure your phone is on the 2.4 GHz network, not 5 GHz. Follow the app prompts exactly: press and hold the Temp and Spin buttons together for 3 seconds to enter connection mode.
If That Didn't Work
Power cycle the washer. Unplug it for 5 minutes. This resets the WiFi module. Also try forgetting the network on the app and starting the setup process over from scratch.
Heads Up
The Smart Things functionality is basic: remote start, cycle monitoring, diagnostics. It does not add new wash cycles. If your router uses WPA3 encryption, you may need to set it to WPA2/WPA3 mixed mode.