Xiaomi Mi A2 unable to connect to wifi on new smart modem

[Aeromanny]

Hi all, 

I received a new smart modem and for some reason one of our devices cannot connect to the wifi (Xiaomi Mi A2)

It saves the password and SSID however does not connect. The system software is up to date and it connects to other hotspots with no issues. We have tried restarting the device and smart modem and are still experiencing the issue. Anyone have any idea how to solve this? 

[cf4 · Accepted solution]

It could be Protected Management frames that is stopping the connection. To disable PMF log into modem (http://192.168.0.1, password is Telstra), go to Advanced > WiFi > 2.4 GHz, scroll down and look for Protected Management Frames or Wi-Fi PMF, set to off or disabled and save settings. If phone is dual band repeat for 5GHz WiFi.

If still can'r connect try disabling Band steering in the 2.4 GHz WiFi settings. This adds -5G to the 5GHz WiFi name.

If still can't connect try changing security type from WPA2 PSK to WPA+WPA2 PSK.

[Aeromanny]

Thanks! Switching on the WPA+WPA2 PSK has resolved the issue.