I bought a new C80 to use with my existing network at home. 2.4Ghz band is working fine but 5Ghz band does not show up on devices at first. But If change the mode to wireless access point instead of router mode and turn on the smart connect only then I'm able to get connected at 5Ghz. Both my following devices support 5Ghz.

1- MacBook Pro M1 2020

2- OnePlus 8

Even after changing to wireless AP mode and turning on smart connect I'm able to connect with Macbook. I can't get a 5Ghz connection with OnePlus8. I'm in no way able to see a separate AP for 5Ghz if I turn of the smart connect. I only get a 5 Ghz connection if I have enabled smart connect and wireless AP mode instead of router mode.

Is my router faulty or am I missing something.

Update: Smart connect has no effect it only works if the SSID for 2.4 and 5Ghz are the same which is case in smart connect. Even if I turn off the smart connect but keep the SSIDs same it keeps working but on only one device. If change the SSID it stops working. When the main 5Ghz AP stops working given the SSID does not match with 2.4Ghz, then even if have some guest 5 GHz AP running those also vanish. So all in all if the SSID for 2.4 GHz and 5GHz is not same then C80 stops all 5 GHz SSIDs.