Cannot insert password after update

The laptop was working perfectly fine on Saturday evening.

I shut down that evening & chose the option to update. Since then I am unable to insert my password to log on as the letters don't work. The same is true for plugging in a keyboard which works perfectly fine on a desktop. The laptop does not seem to register the letters, the rest it does. 

It asked me to type in a code when I inserted my password incorrectly too many times, strangely the letters on the keyboard works then - both the laptop & the plugin keyboard.

Does anyone have any other ideas as to how to overcome this?