How do i make my paintball script shoot the paintballs to the players mouse position?

I'm trying to make my paintball gun shoot to the players mouse position but it shoots the underneath the player and doesn't go to the mouse. How do i fix this?

The script is in a GUI and I want to keep it like that.

Here is my whole script :

colors = {45, 119, 21, 24, 23, 105, 104}

function fire(v)

    print'shot'

    local vCharacter = game.Players.LocalPlayer.Character
    local vPlayer = game.Players:playerFromCharacter(vCharacter)

    local missile = Instance.new("Part")



    local spawnPos = vCharacter.PrimaryPart.Position



    spawnPos  = spawnPos + (v * 8)

    missile.Position = spawnPos
    missile.Size = Vector3.new(1,1,1)
    missile.Velocity = v * 100
    missile.BrickColor = BrickColor.new(colors[math.random(1, #colors)])
    missile.Shape = 0
    missile.BottomSurface = 0
    missile.TopSurface = 0
    missile.Name = "Paintball"
    missile.Elasticity = 0
    missile.Reflectance = 0
    missile.Friction = .9

    local force = Instance.new("BodyForce")
    force.force = Vector3.new(0,90,0)
    force.Parent = missile

    --Tool.BrickCleanup:clone().Parent = missile

    local new_script = script.Parent.SnowGun:clone()
    new_script.Disabled = false
    new_script.Parent = missile

    local creator_tag = Instance.new("ObjectValue")
    creator_tag.Value = vPlayer
    creator_tag.Name = "creator"
    creator_tag.Parent = missile



    missile.Parent = game.Workspace

end




function activate()


    local character = game.Players.LocalPlayer.Character
    local humanoid = character.Humanoid
    if humanoid == nil then
        print("Humanoid not found")
        return 
    end

    local targetPos = humanoid.TargetPoint
    local lookAt = (targetPos - character.Head.Position).unit

    fire(lookAt)

    wait(.5)


end


mouse = game.Players.LocalPlayer:GetMouse()
mouse.Button1Down:connect(activate)