Diagnosis
The most common cause is the purifier not being in pairing mode or a 2.4 GHz/5 GHz network conflict.
How to Fix It
Confirm the purifier's front light is slowly blinking blue. If not, hold the WiFi button on the back for 5 seconds until it does. Ensure your phone is connected to a 2.4 GHz WiFi network, not 5 GHz. Disable any VPN on your phone during setup.
If That Didn't Work
Perform a full reset. Unplug the purifier. Hold the front power button for 30 seconds while it's unplugged. Plug it back in and restart the setup process in the app.
Heads Up
The Molekule Air Pro does not support WPA3-only security or enterprise networks. Use WPA2 on your router for setup.