Example of two people ruining a ranked game.

So, I'm playing Amumu, I'm hella fed, suddenly, Karma starts flaming me. Obviously I talk back, cus im like 10/2/7, and she's talking shit. Obviously I should have just mute her, but we we're all so fed this game was a free win. or thats what I thought. Karma sold all her items, ran it down mid. Her Jhin duo bout all swiftness boots and also ran down mid. Here's screenshots for proof:

https://gyazo.com/52ca10d5fc0ff84e93b0bb60078c5db9 (They sold someof their items last second to make it look less bad)

https://gyazo.com/fd438a35c4886d65ed34cdc8bbfee0a8 (Out gold lead was 9.1k, if they weren't trolling and had attacked the nexus we would won)

If I don't get a message syaing these two players are Ip banned, then idk what to say. People say the League community is the most toxic one on the internet, I never believe it until this happened to me.