Is it possible to report somebody for harassment post-game?

I was having a bad day and was on a loss streak and happened to land in a game with an incredibly toxic ADC and a support which I muted early in the game because of the toxic things they were saying. After the match was over, I got a friend request from the ADC which I accepted it. After accepting the friend request the ADC proceeded to call me a "piece of shit r%%%%%%%%%% told me to "learn the fucking game" and then unfriended me. I reported both of them after the game ended but I was wondering if what the ADC did was punishable? I have a screenshot of the conversation but I don't know if I am allowed to post it. Thanks in advance.
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