Exact same problem :)

How did you fix it?

You'll need replacement switches, new mouse feet, a screwdriver, and soldering iron. Order d2fc-f-7n switches online, get at least 2. In my exp, the sides switches break sooner, as they are lower quality. Replace both, as it's a matter of time until the other fails. make sure you buy the thicker replacement feet online, as the thinner ones are just covers for worn pads, not full replacements. I got everything off aliexpress, seems better for very small items.

Similar mouse, exact same problem. My fix was to take off the top of the switches, take out the spring and re-tense it. It's a fiddly, annoying process, as seen here: https://www.youtube.com/watch?v=eDoXMJyimDU Did this twice (each fix lasted about a year) then bought a zowie lol

I've tried replacing them but the switches seem to be LG specific (3-pin, odd height). I ordered a few different switches but none of them worked. I tried asking LG the part number for the switches but they refused to provide it.

Logitech mouse M 100. This is my third one. Used daily, they last about two years. Cost ~CDN $12-14. The first two, the left click stopped working. About one year on number three. Works like I expect each day.

I found an easy fix for this problem. You pretty much breathe your hot breathe into the mouse from the gap. Make sure it's a warm and humid inside the mouse, leave it for a bit and then blow air into the mouse. I've been fixing this mouse for 2 years now like this. I have 2 backups of the same mouse that I haven't opened yet. I play CS:GO. and I'm not even joking about this fix.

I had one where the scroll wheel physically degraded beyond acceptable use after about two years, fixed by replacing it with an aliexpress ordered replacement wheel. (The replacement wheel I had seems to no longer be in listings but they have what curiously looks like a custom compatible one instead made out of metal)

I used the switch from dpi button i think to replace the broken right button.