Gaming Notebooks

The "A" key on my Omen X 17t laptop now no longer provides any input to the computer.  The other keys work fine, so I do not think that this is a software problem.  The key itself does not appear to be stuck; it depresses to the same extent that other keys do, snaps back, and makes the same clicking noise.  However, when pressed the computer does not register that the key has been pressed.

It's worth noting that at first the key would work unreliably.  That is, in the hour before this happened it would occasionally not register a key press and then work fine for several presses after that.  Then it stopped working completely.

I have tried clearing any debris from around or under the key, and there doesn't seem to be anything major there (though of course there's probably some dust and stray hairs/eyelashes, etc. as you usually get with a keyboard).  I haven't removed the key because I am worried about breaking the key and not being able to put it back on the keyboard (this happened to me with a previous laptop). 

Is there anything which could be causing this other than something physically jamming the key?  And if it is something under the key which I need to remove by removing the key, are there are any guides or tips for how I can do that without damaging the keyboard?