I got a custom 15 inch MAINGEAR Element back at the beginning of 2020 (just before the pandemic hit - had I known it would hit, I would have gotten a desktop, because since then my laptop has spent 95% of its life sitting on my desk). Recently, this past Christmas, I got a new M.2 drive, and when I closed up the laptop after installing it, I noticed that the bottom panel was pushed out a tiny bit near the touchpad-end of the laptop. I initially thought that I reinstalled the panel incorrectly, but when I took it off and put it back on again, it was still like that. I thought that it might be something with the battery, so I decided that I'd keep an eye on it to see if it got any worse.
Today, I was sitting at my desk and idly looked at the light bar at the bottom of the laptop and thought "Huh... wasn't there only one line there?" - Upon closer inspection, I realized that the second lighted line I was seeing was the light shining through from the inside of the casing, being visible as the bottom panel has been pushed out about 4mm / roughly 1/8 of an inch.
Needless to say, I'm extremely alarmed by this - in about 2-3 weeks, it's gone from a hairline gap that you'd only really notice if you pushed down on that part and felt it pop back into its normal position, to now being so wide that I'm seeing the back side of the light bar shining through. I want to avoid having to send it off for repairs if I can help it, as I need to use this for my college classes, and not to mention personal data on the laptop; I'm confident enough in my skills that I believe I can replace the battery myself (I mean, if I can replace an iPhone battery, installed new RAM and an additional M.2 drive, and helped my friend assemble his desktop, I should be able to handle a laptop battery), however I can't seem to find where to buy one. My laptop should work fine for a little while longer, but I want to replace its battery as soon as possible.