I just finished playing through a match where things started acting strangely towards the end. I seemed unable to kill anyone I was after, despite standing right beside them. Whenever I pressed the x button, they would dodge the blow and it would be like this even if I kept at it for a while. The same thing happened when someone tried to stun me, I would just dodge out of the way without doing anything at all, it was a little bizarre.
I used a smoke bomb a few times and even when my target was coughing, they would dodge just as soon as I pressed X, again, same thing happened to me when a smoke bomb was used on me.