I really don’t know what are you doing with your notebooks. Every new notebook is delivered with clean preinstalled operating system (recovery image) and FN keys (flash cards) MUST work properly.
Later, when you install your own stuff or configure OS, something may go wrong and flash cards can stop working. On this virtual way it is not easy to say what the problem can be.
Of course, you can try to fix this reinstalling Value Added Package. This software package contains “Flash Cards utility” and it should work again. Before you install VAP remove preinstalled version and restart your notebook.
I don’t know what kind of Windows installation you have installed but everything possible can be responsible for non working flash cards.