I have looked everywhere but I can't seem to find a solution.
I'm trying to connect to my 5Ghz router from Ubuntu 18.04 but it can't see the network. It will only see the 2.4ghz network and even other 5ghz networks that are not mine.
To be more specific, my wifi card is a TP-Link Archer T9E (AC 1900) and my router is the Portal WiFi . This router has "FastLanes" that uses DFS wifi channels to avoid congestion. Currently it is using Channel 100 (it cannot be manually set to a different channel).
My other devices connect fine to the 5ghz network, including the same computer I'm trying to connect when using Windows, so it is not a problem with the adapter. I'm using the proprietary driver obtained through Ubuntu Software & Updates.
If anybody could help me make this work I would appreciate it greatly.