Fn key is reversed, no option in BIOS to change its behavior

[deim]

In order to get to use normal F1-F12 keys I need to hold Fn key. This should not be default setup, but somehow it is. The support page says that in order to revert the Fn key I need to uncheck the option "Launch Hotkeys without Fn Keypress" however there is no such option on my BIOS, even after I upgraded it to the latest version (1.8.3)

Here are the screenshots of BIOS screen:

How do I reverse it? I need to use the F keys on a regular basis.

[deim]

I found there is a combination of Fn+Shift that works as a "Fn Lock". The problem is, that combination just disables the Fn key alltogether. Is there a way to have a normal Fn key behavior?

Normal in a way that it's not pressed by default, but I can press it whenever I need a additional keys - you  know, like in any other kind of laptop?