I was hacked, and I didn't know it until last night, I checked my elo *trash right now don't judge* and it said I played a ranked game, "Hmm, this is interesting, on the 11th it said i played graves." However, the only ADC i play is ashe and draven, I don't wish to remove the loss or anything, but is their a way I can prevent this from happening? I restored my pc to factory settings etc. But I never downloaded a thing or visited any website, is there a way I can find out who did this?
P.S. i know i didnt play this game, i was on a date at the movies with my gf all day then stayed till late and didnt play when i got home.

submit a ticket, change your pass etc