Game logged out right after winning

So I won a game last night by 3-2. Had 4 bars of connection and there were no lags (surprisingly). But somehow after the game ended I got logged out all of a sudden and when I logged back in it says I lost by 3-0?? I never encountered this before. What exactly was the issue? My friend told me it might he a hacker but idk. Does anyone have the same issue? Sorry I don't have video/photo evidence cus I was too flabbergasted at the time lmao