Please do try these troubleshooting steps that may help.
- First is to uninstall/reinstall the keyboard driver.
- Go to Device Manager and uninstall the keyboard driver.
- Reboot the laptop once the driver has been uninstalled and it should reinstall the driver automatically.
- After the reboot do test it again and see if the same problem will persist or not.
- If it will still not work do try changing the keyboard language and settings.
- If changing keyboard layouts will not work, connect an external USB keyboard and see if it will work normally or not.
- Do run System Restore if an external USB keyboard will work normally. Restore the laptop back to an earlier date or time before the problem even happened.
- If System Restore will still not work you'll need to reinstall Windows.