my script dose slow down the player/npc no errors how do i fix ?

mast =player who dose not get effected

local Players = game:GetService("Players")
local give = true
local g =  Instance.new("ScreenGui")

script.Parent.Touched:Connect(function(hit)
    local mast = script.maker.Value
    local player = Players:GetPlayerFromCharacter(hit.Parent)
if mast then
    else
end
    if not player then return end
    if give then
        give = false
        local f = Instance.new("Frame")

        f.Parent = g
        g.Name = "2d3x2"
        f.Size = UDim2.new(22, 1500,22, 15006)
        script.slowdown:Play()
    f.Position = UDim2.new(-0.008, 0,0, 0)
    f.BackgroundColor3 = Color3.fromRGB(0, 0, 0)
        g.Parent = player.PlayerGui
        f.BackgroundTransparency = 1
g.Name = "214sw21"
    for i = 1,15 do
        wait(.4)
    f.BackgroundTransparency =  f.BackgroundTransparency - 0.05


    wait(9)
        g:Destroy()
    end

    end
end)

script.Parent.Touched:Connect(function(hit)
    local humanoid = hit.Parent:FindFirstChild("Humanoid") 

            local mast = script.maker.Value
            if mast then
            else
                end
    if (humanoid ~= nil)  then  
        else
        repeat 
            wait(.5)
        humanoid.WalkSpeed = humanoid.WalkSpeed -.2
        until humanoid.WalkSpeed == 0
        wait(12)
        g:Destroy()
        humanoid.WalkSpeed = 16


end
end)