F1-f12 functions on laptop (louder quieter etc) only still by key combination fn + fxx?

I bought myself a laptop some time ago. At the beginning everything worked as usual with the upper control panel (ie louder keys, etc., where the f1-f12 keys are).

Now this panel only works by pressing it together with the "fn" button, which means if I want to turn it down I have to press fn + f2. Otherwise I press only the f2 key and all that, although I have not adjusted anything (probably I've already done that accidentally, otherwise I would not have this problem).

How can I undo this?

Which model? There's often a Fn-Lock to toggle. Try Fn + ESC.

Not at all.

It was wrong before, now it is right.

The F-keys as such are also needed for normal keyboard shortcuts in the programs.

The Fn-key is there, that just not the actual F-key is triggered, but the second occupation, the laptop manufacturer has come up with.

Many Thanks! It works again!