My Optus Ultra Wifi Modem (white with 4g backup) has wifi but no internet connection on its 5GHz setting/connection...
Yet it has a wifi connection AND an internet connection on 2.4GHz setting
Solved! Solved: Go to Solution.
If you have WiFi but not internet its probably because the device has an incorrect manually set gateway.
Delete the 5GHz setting on your device and re-enter them and connect via the default DHCP setting instead of static.