Hi,
Please do try these troubleshooting steps that may help.
- First is to uninstall/reinstall the keyboard drivers from Device Manager.
- If the same problem will persist try using a USB keyboard and see if it will work normally or not.
- If using an external USB keyboard will work normally that could mean it's the built in keyboard that is not working properly.
- I would suggest checking the ribbon cable as well that connects the keyboard to the motherboard.
- And lastly replacing the keyboard itself if all these will not work.