Did you try rebooting the computer? Sometimes that is all you need. I would also check your keys for any one with lock or a lock symbol.
Should none of this work, then you may need to connect an external keyboard to get into the computer and then go to "Start" and then search box, type in "Ease of Access Center". Now check the settings in there.
Should that not resolve it, try the following...
1. Uninstall the keyboard driver.
2. Reboot the computer (without reinstalling the driver).
3. When it restarts, it should reinstall the driver on its own.