Internet constantly dropping during Nexus Blitz game

https://cdn.discordapp.com/attachments/409550622656823304/480992177011425290/unknown.png

(This is something I use to take a note of my ping before games start. Here, it shows my ping before the first disconnect and then the complete crash of my computer's connection to any router when it says "PING: transmit failed"):

I was playing Nexus Blitz about 10 minutes ago (game ended 10 mins ago, we lost by a large margin btw) and when the game started, my computer's connection dropped. This isn't the most uncommon thing (but it only happens with League and NO OTHER GAME) so I started resolving the issue. Usually a quick Troubleshoot or Disconnect/Reconnect helps... but all of a sudden, my computer's entire wireless connection just drops. My computer can't even locate other nearby routers/modems. So, after a quick troubleshoot, I find every other router except for my own. All of a sudden, my own router pops up on the list and I reconnect. Thing is, this is an old box we recently replaced and I'm just stunned over how a Wi-Fi connection for a box that was replaced like 2 days ago is on the list. I reconnect to it (needing to type in the password for it even though my computer already knew this router but w/e).

I start playing and then, the same thing happens except now, both my new router name and the old one that was replaced weren't on the list. After a while, the old one pops up and I reconnect. I'm getting flamed by my Vayne at this point (I assumed so but I muted them earlier on before Lucian randomly says "Report Vayne toxic"). I play a bit more, then it happens one more time and I reconnect to the old name, leaving the game because I still haven't reconnected on screen which means the game already ended. I log back in happy that I didn't receive a punishment for this but still, why is League the only game my disconnects happen with? There could be a storm outside that's borderline hurricane and I can play Starcraft 2/OverWatch/Steam/etc with ease while I get random disconnects on League very often.

(P.S., I still can't find the new router on my list. I'm currently using the old one even though the box was damaged and replaced by a new one. Unless SOMEHOW someone is up at 2:30AM and decided to randomly change the new box's settings or something, this doesn't make sense.)