Easy :TweenSizeandPosition script only works in studio?

So, I made a very simple Gui Tweening script that works very well in studio and looks pretty nice. But, when I go into game or test on server, literally nothing happens. Nothing appears in the output or anything. Here is my script:

local b = 0
local c = script.Parent.InfoBox
local d = script.Parent.Credits
local e = script.Parent.MuteButton
local f = script.Parent.GamepassStore
local g = script.Parent

        c.Visible = false
    d.Visible = false
    e.Visible = false
    f.Visible = false

g.Size = UDim2.new(0,0,0,0)

function a()
    b = b + 1
    if b == 1 then
    print("boop")
    script.Parent.Parent.Image = "rbxassetid://0"
script.Parent.Position = UDim2.new(0.5, 0, 0.5, 0) 
script.Parent.Size = UDim2.new(0,0.1,0,0) 
script.Parent:TweenSizeAndPosition(UDim2.new(0, 1200, 0, 100), UDim2.new(1, 0, 0, 0), "Out", "Sine", 1) 
wait(1)
script.Parent.Parent.Image = "rbxassetid://93012106"
    c.Visible = true
    d.Visible = true
    e.Visible = true
    f.Visible = true
print("boop successful")
end
if b == 2 then
        b = 0
        script.Parent.Parent.Image = "rbxassetid://0"
            c.Visible = false
    d.Visible = false
    e.Visible = false
    f.Visible = false
            script.Parent:TweenSizeAndPosition(UDim2.new(0, 0, 0, 0), UDim2.new(0, 0, 0, 0), "In", "Sine", 1)
            wait(1)
            script.Parent.Parent.Image = "rbxassetid://93012106"
    end
end


script.Parent.Parent.MouseButton1Click:connect(a)

It's a very simple script, does anyone know why it won't work?