Many ASUS WiFi routers have an "airtime fairness” feature which can make it difficult for you to connect your Mill WiFi device.
For successful connection of your Mill WIFi device do the following:
Go to ASUS: Wireless menu --> Professional Tab --> Airtime Fairness --> Deactivate Airtime Fairness
On some ASUS routers there is a feature called "Smart Connect" that forces Mill WiFi devices over to 5GHz if the signal strength is stronger than the required 2,4Ghz signal. This can cause problems for Mill WiFi heaters because 5Ghz is currently not supported. We therefore recommend that this “Smart Connect” function is deactivated when connecting Mill WiFi heaters, and rather reactivate the after your Mill WiFi heater is connected successfully.