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)