Hi JINGWEI WU,
Since the 6 GHz SSID is still visible on your Surface Pro 11 and other devices can connect successfully, the issue may be related to how the current wireless adapter configuration is interacting with the recent update rather than a problem with the router itself.
As an additional check, try disabling and re-enabling the Qualcomm FastConnect 7800 adapter:
- Open Device Manager, expand Network adapters.
- Right-click Qualcomm FastConnect 7800 and select Disable device.
- Wait 30 seconds, then Enable device again.
- Restart the Surface and test the 6 GHz network.
You can also check Settings > Windows Update > Advanced options > Optional updates for any newer Surface or Qualcomm wireless driver that may not have installed automatically.
If the issue continues, collecting a wireless report may help identify whether the connection is failing during authentication or association - run this command in Command Prompt (Admin): netsh wlan show wlanreport
This generates a report in C:\ProgramData\Microsoft\Windows\WlanReport that can provide more insight into the connection failure.
I hope this helps point you in the right direction. Let me know if you need further assistance, feel free to ask me by clicking "Add Comment" or "Add Answer" if you cannot add comment so your response will be visible. Thanks for your effort.
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