Roblox's Whistle occurrence

So I have reported that there was this player who keeps appearing on my games yesterdayeidsvsnf I went on to record every gameplay after I did that but vnpelo I've announced his shenanigans but eventually he came back, I do not know if this is from the game itself or was Roblox in my device hacked to do such things, but he probably wasn't happy at that time. he never appeared again after