I don't get how this is fair?

Okay so I got afk penalties yesterday and it annoyed me so I finished all of them. Then my friends asked me to do a ranked with them and my laptop crashed and by time I got back on the match was over. Then it said I have 5 afk penalties from leaving a recent match. Is that fair that I get more penalties for something I didn't do? Also is there a way Riot can fix it or cancel the penalties?