How do I make ko's work with sword?

When I kill someone with a sword the ko's won't work but the wipeouts work How do I fix this?

PLAYERS={"PLayer"}
function check(name)
        if #PLAYERS == 0 then return false end
        for i = 1,#PLAYERS do
                if (string.upper(name) == string.upper(PLAYERS[i])) then return true end
        end
        return false
end
function onHumanoidDied(humanoid, player)
    local stats = player:findFirstChild("leaderstats")
    if stats ~= nil then
        local deaths = stats:findFirstChild("Deaths")
        deaths.Value = deaths.Value + 1
        local killer = getKillerOfHumanoidIfStillInGame(humanoid)
        handleKillCount(humanoid, player)
    end
end
function onPlayerRespawn(property, player)
    if property == "Character" and player.Character ~= nil then
        local humanoid = player.Character.Humanoid
        local p = player
        local h = humanoid
        humanoid.Died:connect(function() onHumanoidDied(h, p) end )
    end
end
function getKillerOfHumanoidIfStillInGame(humanoid)
    local tag = humanoid:findFirstChild("creator")
    if tag ~= nil then
        local killer = tag.Value
        if killer.Parent ~= nil then
            return killer
        end
    end
    return nil
end
function handleKillCount(humanoid, player)
    local killer = getKillerOfHumanoidIfStillInGame(humanoid)
    if killer ~= nil then
        local stats = killer:findFirstChild("leaderstats")
        if stats ~= nil then
            local kills = stats:findFirstChild("Kills")
            if killer ~= player then
                kills.Value = kills.Value + 1
            else
                kills.Value = kills.Value - 0
            end
            local points = stats:findFirstChild("Points")
            if killer ~= player then
                points.Value = points.Value + 1
            else
                points.Value = points.Value - 0
            end
        end
    end
end
function onPlayerEntered(newPlayer)
    local stats = Instance.new("IntValue")
    stats.Name = "leaderstats"
    local kills = Instance.new("IntValue")
    kills.Name = "Kills"
    kills.Value = 0
    local deaths = Instance.new("IntValue")
    deaths.Name = "Deaths"
    deaths.Value = 0
    local points = Instance.new("IntValue")
    points.Name = "Points"
    if not (check(newPlayer.Name)) then
        points.Value = 0
    else
        points.Value = 10000
    end
    kills.Parent = stats
    deaths.Parent = stats
    points.Parent = stats
    while true do
        if newPlayer.Character ~= nil then break end
        wait(5)
    end
    local humanoid = newPlayer.Character.Humanoid
    humanoid.Died:connect(function() onHumanoidDied(humanoid, newPlayer) end )
    newPlayer.Changed:connect(function(property) onPlayerRespawn(property, newPlayer) end )
    stats.Parent = newPlayer
end
game.Players.ChildAdded:connect(onPlayerEntered)