My Nokia 8 won't connect to 5Ghz WiFi. Can you explain how several reboots solved the issue?
The first place to start is make sure the 2.4GHz and 5GHz frequencies have separate SSIDs, it is well known that sharing SSIDs can cause more problems than it is worth.
If you have done that and you cannot see a 5GHz SSID then maybe the phone is faulty, i know it wont really bother to waste battery power scanning for a new access point when it is connected to a perfectly good one already but if you knock Wi-Fi off and back on again it should scan everything.
Different SSIDs are in place and visible :-)
my case is that when knocking Wi-Fi off and back on while scan wireless networks 5GHz SSID are not listed.
I have tried, without success, changing the channel and channel width. WPAs encription and authentication methods, but nothing. even tried different routers.
No sucess! not even with phone in safe mode.
I don't know then my friend, maybe the phone is faulty after all.
I'm having a similar issue since the update. 5GHz is the preferred band, but it will only connect for about a second, and then defaults to 2.4GHz. If I delete the 2.4GHz network, it still drops the connection on 5GHz and stays unconnected. It's not a signal strength issue, as I can be on top of the router and the problem persists.
Definitely an update bug, I think, as wi-fi does work generally. I'll wait until the next update to see what happens.