Paintball gun kills players on the same team?

I was working on a paintball game until i found out that the gun kills people on the same team which is not what i want

ball = script.Parent
damage = 100

function onTouched(hit)
    local humanoid = hit.Parent:findFirstChild("Humanoid")
    local playername = humanoid.Parent.Name
    local playerteam = game.Players['playername'].Team.Team


    if hit:getMass() < 1.2 * 200 then

    end
    -- make a splat
    for i=1,3 do
        local s = Instance.new("Part")
        s.Shape = 1 -- block
        s.formFactor = 2 -- plate
        s.Size = Vector3.new(1,.4,1)
        s.BrickColor = ball.BrickColor
        local v = Vector3.new(math.random(-1,1), math.random(0,1), math.random(-1,1))
        s.Velocity = 15 * v
        s.CFrame = CFrame.new(ball.Position + v, v)
        ball.BrickCleanup:clone().Parent = s
        s.BrickCleanup.Disabled = false
        s.Parent = game.Workspace
        --game.Debris:AddItem(s, 5)

    end


    if humanoid ~= nil and playerteam == 'Red' then
        tagHumanoid(humanoid)
        humanoid:TakeDamage(damage)
        wait(2)
        untagHumanoid(humanoid)
    end

    connection:Disconnect()
    ball.Parent = nil
end

function tagHumanoid(humanoid)
    -- todo: make tag expire
    local tag = ball:findFirstChild("creator")
    if tag ~= nil then
        local new_tag = tag:clone()
        new_tag.Parent = humanoid
    end
end


function untagHumanoid(humanoid)
    if humanoid ~= nil then
        local tag = humanoid:findFirstChild("creator")
        if tag ~= nil then
            tag.Parent = nil
        end
    end
end

connection = ball.Touched:connect(onTouched)

wait(8)
ball.Parent = nil