report a bug

hey i'm really angry because i've been playing champion matches all evening to get rewards and then my game crashes and one of the matches crashes out of nowhere? which is really weird but it was only one match so i let it be but then now i'm playing against a cheater who made my game freeze and all of a sudden it was half time and he was leading 1-0 without even having played do you think it's really bad that things like this still happen so now i can't get my rewards that i've been playing half the evening because of a lot of bugs?