I assume you mean this is for your server?I have also this error and i just kill one, i get : 1kill : +2, 2kills: +4 .... and so far.
any solution for this?
Only activate the mutator in one place. Either put it in the .bat file or put it in the kf.ini , not both.
I suggest in the kf.ini . Under
[Engine.GameEngine]
put
ServerActors=MutKillMessageV2.MutKillMessage
ServerPackages=MutKillMessageV2