To split the 2.4 GHz and 5 GHz networks, you must turn Smart Connect off.

Open the Mercku App > Select Settings > Select Wi-Fi Settings > Click Smart Connect to turn it off.

Once Smart Connect is off, you will see two networks - the 2.4 GHz network (will have the same SSID), and the 5 GHz network (SSID - 5G). The password for both networks will remain the same.