Case 1: Cannot see any 5G Wi-Fi.
Suggestions:
1. Disable the old wireless adapter.
To disable the other adapters, click on Control Panel-> Network and Internet-> Network and Sharing Center-> Change Adapter Settings on the left side. Only keep the Cudy wireless adapter on and check the Wi-Fi list again if you can see the 5G Wi-Fi or not.
Or go to Device Manager and find old wireless adapter, then disable it.
2. Update the latest driver from the official website.
Case 2: Cannot see the 5G Wi-Fi of your router
Suggestions:
1. Disable the old wireless adapter as Case 1.
2. Update the latest driver from the official website.
3. Change the wireless channel on the router’s web interface.
Here we take the Cudy router as a demonstration.
General Settings->Wireless->5G Wireless Settings->Channel.
It might be affected by DFS, for the details, please refer to:
https://wifinigel.blogspot.com/2018/05/the-5ghz-problem-for-wi-fi-networks-dfs.html