My up and down keys aren't working

My up and down arrows stop working every so often, I haven’t noticed anything which triggers it. They aren’t working in any program and my left and right arrow keys are working fine. If I restart my computer they will work again but that seems like a lot of effort and I would have thought there is some other way to turn them back on. I have tried the scroll-lock on the on-screen keyboard but that’s not the problem, I have seen a few places that I should try the f7 key but on my hp the f7 key decreases the volume, I have tried fn + f7 to see if that would work but still doesn’t seem to do the trick.

Any idea?

Please help.

I didn’t find the right solution from the Internet.


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