here's something that was posted right below your post.. see if it works for ya
The Fn key is locked
If you're writing numbers instead of letters when you press the keyboard of your laptop and you must hold down the Function key (Fn) to write normally.
This is due to the fact that the digital lock is activated. To solve this, simply press the Fn+Numlk or depending of the model, press the button or Fn + Shift +Numlk