Got connection issues while playing only League | Help/Tips would be appreciated

It's been months since I played League because of this but the problem is still here. So basically, whenever I start a game, everything is fine until around 5th minute or so. After 5th minute my ping rises to around 1,000-10,000 and once got so high as 25,000. Those thousands of ping last for about 7 minutes, but can last up to 12. After that, the ping lowers itself to around 500 (Still unplayable) and stays like that for the rest of the game. All that I've pointed out has been pretty much consistent. Everytime around 5th-7th minute it begins and "calms" around 14th-18th minute. Works on any map and gamemode. Those pings spikes also utterly destroy other connection, pretty much destroying Discord too.

Also be aware that this happens literally only while playing League. No other game/application has ever replicated what I can pretty much bet my life savings on happening in League.

Got any ideas or tips to fix this? I am literally not playing League just because I am not allowed to by this

Edit: Also just noticed I put this in the wrong board. So would be appreciated if this was moved into the correct one since I do not believe I can change that. Thank you