How to fix a broken key?

Sep 19, 2018
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There's a key on my keyboard that stopped working out of nowhere. I would press it and nothing would happen, so following the advice I'd seen online, I decided to take the key off to blow out dirt from underneath they key or whatever.
I did this and the key still fails to work. I tried to put the cap of the key (or whatever it's called, the part of the key where the letter is written) back on and succeeded only in disattaching the O shaped part of the retainer on the key. My computer is an asus Transformer Pro but all the help articles I've seen online for this sort of thing are for Dell keyboards and the parts look too different for those to help.
Now not only do I need help finding out how to put the key back together but I need to know how to get the key working again, and no, I didn't spill anything on it.
Thanks x-x