Why won't my screen textbox gui work?

I created a script for a lockdown. When the players joins I want the GUI to be created and when the red button is hit I went near the end of it to display the GUI. Please help me. Where I put

--<

Is where the errors are.

local L1 = workspace.Light1
local L2 = workspace.Light2
local L3 = workspace.Light3
local L4 = workspace.Light4
local L5 = workspace.Light5
local L6 = workspace.Light6
local L7 = workspace.Light7
local L8 = workspace.Light8
local d1 = workspace.Door1
local d2 = workspace.Door2
local d3 = workspace.Door3
local P = workspace.Plat
local But = workspace.Button
local s = workspace.Screen
game.Players.PlayerAdded:connect(function(player)
    local s = Instance.new("ScreenGui")
    s.Parent = player.PlayerGui
    wait(.1)
    local t = Instance.new("TextBox")
    t.Parent = player.PlayerGui.ScreenGui
    t.BackroundTransparency = 1
    t.TextTransparency = 1
    t.Text = "Evacuate to sector J Immediatly!"
    t.TextColor3 = Color3.new(255, 85, 0)--<
    t.BorderColor3 = Color3.new(255, 255, 0) --<
    t.BackroundColor3 = Color3.new(0, 0, 0) --<
    t.BorderSizePixel = 10 --<

end)
function onClick()
    But.ClickDetector:Remove()
    s.SurfaceGui.TextBox.Text = "Lockdown In Progress"
    s.SurfaceGui.TextBox.TextColor3 = Color3.new(255, 0, 0)
    game.ServerScriptService.Dublicate.Disabled = true
    game.workspace.Sound:Play()
    wait(3)
    L1.SurfaceLight.Color = Color3.new(255, 0, 0) 
    L2.SurfaceLight.Color = Color3.new(255, 0, 0) 
    L3.SurfaceLight.Color = Color3.new(255, 0, 0) 
    L4.SurfaceLight.Color = Color3.new(255, 0, 0) 
    L5.SurfaceLight.Color = Color3.new(255, 0, 0) 
    L6.SurfaceLight.Color = Color3.new(255, 0, 0) 
    L7.SurfaceLight.Color = Color3.new(255, 0, 0) 
    L8.SurfaceLight.Color = Color3.new(255, 0, 0) 
    L1.SurfaceLight.Brightness = 10
    L2.SurfaceLight.Brightness = 10
    L3.SurfaceLight.Brightness = 10
    L4.SurfaceLight.Brightness = 10
    L5.SurfaceLight.Brightness = 10
    L6.SurfaceLight.Brightness = 10
    L7.SurfaceLight.Brightness = 10
    L8.SurfaceLight.Brightness = 10
    L1.Material = 'Plastic'
    L2.Material = 'Plastic'
    L3.Material = 'Plastic'
    L4.Material = 'Plastic'
    L5.Material = 'Plastic'
    L6.Material = 'Plastic'
    L7.Material = 'Plastic'
    L8.Material = 'Plastic'
    L1.BrickColor = BrickColor.new("Really red")
    L2.BrickColor = BrickColor.new("Really red")
    L3.BrickColor = BrickColor.new("Really red")
    L4.BrickColor = BrickColor.new("Really red")
    L5.BrickColor = BrickColor.new("Really red")
    L6.BrickColor = BrickColor.new("Really red")
    L7.BrickColor = BrickColor.new("Really red")
    L8.BrickColor = BrickColor.new("Really red")
    game.workspace.Sound:Pause()
    game.workspace.sound:Play()
    wait(10)
    game.workspace.sound:Pause()
    game.workspace.Door:Play()
    wait(3)
    d3.CFrame = CFrame.new(87.5, -6, 25.5)
    d2.CFrame = CFrame.new(87.5, 8.5, -82.5)
    d1.CFrame = CFrame.new(31.5, 8.5, -78.5)
    wait(3)
    game.workspace.Door:Pause()
    game.workspace.Evac:Play()
    wait(10)
    game.workspace.Evac:Pause()
    game.workspace.Music:Play()
    wait(115)
    game.workspace.Music:Pause()
    game.workspace.Alarm:Play()
    wait(5)
    game.workspace.Destruct:Play()
    wait(3)
    game.workspace.Destruct:Pause()
    game.workspace.Emerge:Play()
    wait(5)
    game.workspace.Emerge:Pause()
    P.CFrame = CFrame.new(149, 19.5, -318.5)
    game.workspace.D.Script.Disabled = true
    game.workspace.D.CanCollide = true
    game.player.PlayerGui.ScreenGui.BackroundTransparency = 0--<
    game.player.PlayerGui.ScreenGui.TextTransparency = 0 --<
end
But.ClickDetector.MouseClick:connect(onClick)