Hi my name is ***** ***** I will be the expert working with you today to help and resolve the problem you have posted.
I am sorry to hear that you are having such trouble. I will try my best to help you out and resolve the problem as quick as possible.
Is the Fn key physically stuck if yes use a flat small screw driver and lift lightly from the bottom side. Let me know if you find any problem.
is it stuck down or you can still press it and it goes down and comes back to the original position
If you have only one Fn key on the keyboard use the onscreen keyboard to use the Fn key that will work.
If a key stops working that means you need to replace the whole keyboard and if the computer is under one year warranty then you can get it replaced from the service center for free.
You may try removing the keyboard driver from the device manager and then use the mouse to shut down and restart computer. On restart the computer will install the keyboard driver by default and of the key is physically good then it will start working and if not then it needs to be replaced.
Feel free to ask if you have any question.
I hope I’ve provided the information you were seeking.
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