Hello, thank you for reaching out to Microsoft Q&A.
Does your keyboard work normally on the Windows Hello sign-in screen? Are you able to enter your PIN or password there without any issues? Also, does your keyboard work normally in the BIOS setup screen?
If you have an external USB keyboard, temporarily plug it in and check if it works. This will help us to determine whether the problem is with your keyboard or with the system.
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Method 1, Uninstall the keyboard drivers.
Right-click the Start menu > Select Device Manager.
Expand the arrow next to keyboards.
Right-click and uninstall your integrated keyboard drivers, select 'Attempt to remove the driver software for this device' check box and click Uninstall.
Once uninstalled, restart your computer and check if your keyboard is working.
(If you have multiple drivers, uninstall all of them in the lists)
Method 2, Run a system restore.
Right-click the Start menu and select Run.
Copy and paste this command here - rstrui.exe
Click Next.
Select the recent date/time you would like to restore your computer.
Click Next and finish to complete the restoration.
Method 3: Run the System File Checker Utility scan.
Right-click the Start menu and click Task Manager.
Select Run new task.
Type cmd.exe and tick the 'create a task with administrative privileges' check box, and click ok.
Run the command one by one. (just copy and paste)
You can use your mouse to copy and paste the text.
Dism /Online /Cleanup-Image /RestoreHealth
sfc /scannow
Once completed, restart your computer.