Why is my local script inside of StarterGui not working?

Hi, I was wondering why my local script isn't working, I have put it inside of StarterGui.

Here is the script:

local ar = game.StarterGui.WeaponSelectorGUI.MainFrame.AssaultRifle
local cb = game.StarterGui.WeaponSelectorGUI.MainFrame.Crossbow
local gl = game.StarterGui.WeaponSelectorGUI.MainFrame.GrenadeLauncher
local pistol = game.StarterGui.WeaponSelectorGUI.MainFrame.Pistol
local rl = game.StarterGui.WeaponSelectorGUI.MainFrame.RocketLauncher
local smg = game.StarterGui.WeaponSelectorGUI.MainFrame.SMG
local shotgun = game.StarterGui.WeaponSelectorGUI.MainFrame.Shotgun
local sniper = game.StarterGui.WeaponSelectorGUI.MainFrame.Sniper
local turnFoward = game.StarterGui.WeaponSelectorGUI.MainFrame.TurnForward
local turnBack = game.StarterGui.WeaponSelectorGUI.MainFrame.TurnBack
game.ReplicatedStorage.RemoteEvents.RemoveCash.OnClientEvent:Connect(function()
    ar.Text = "weapon is currently unavailable"
    ar.Active = false
    cb.Text = "weapon is currently unavailable"
    cb.Active = false
    gl.Text = "weapon is currently unavailable"
    gl.Active = false
    pistol.Text = "weapon is currently unavailable"
    pistol.Active = false
    rl.Text = "weapon is currently unavailable"
    rl.Active = false
    smg.Text = "weapon is currently unavailable"
    smg.Active = false
    shotgun.Text = "weapon is currently unavailable"
    shotgun.Active = false
    sniper.Text = "weapon is currently unavailable"
    sniper.Active = false
    turnFoward.Text = "this button is currently unavailable"
    turnFoward.Active = false
    turnBack.Text = "this button is currently unavailable"
    turnBack.Active = false
    wait(300)
    ar.Text = "Assault Rifle"
    ar.Active = true
    cb.Text = "Crossbow"
    cb.Active = true
    gl.Text = "Grendade Launcher"
    gl.Active = true
    pistol.Text = "Pistol"
    pistol.Active = true
    rl.Text = "Rocket Launcher"
    rl.Active = true
    smg.Text = "SMG"
    smg.Active = true
    shotgun.Text = "Shotgun"
    shotgun.Active = true
    sniper.Text = "Sniper"
    sniper.Active = true
    turnFoward.Text = "Turn Forward"
    turnFoward.Active = true
    turnBack.Text = "Turn Back"
    turnBack.Active = true
end)

updated code:

local PlayerGui = game.Players.LocalPlayer:WaitForChild("PlayerGui")

local ar = PlayerGui.WeaponSelectorGUI.MainFrame.AssaultRifle
local cb = PlayerGui.WeaponSelectorGUI.MainFrame.Crossbow
local gl = PlayerGui.WeaponSelectorGUI.MainFrame.GrenadeLauncher
local pistol = PlayerGui.WeaponSelectorGUI.MainFrame.Pistol
local rl = PlayerGui.WeaponSelectorGUI.MainFrame.RocketLauncher
local smg = PlayerGui.WeaponSelectorGUI.MainFrame.SMG
local shotgun = PlayerGui.WeaponSelectorGUI.MainFrame.Shotgun
local sniper = PlayerGui.WeaponSelectorGUI.MainFrame.Sniper
local turnFoward = PlayerGui.WeaponSelectorGUI.MainFrame.TurnForward
local turnBack = PlayerGui.WeaponSelectorGUI.MainFrame.TurnBack

game.ReplicatedStorage.RemoteEvents.RemoveCash.OnClientEvent:Connect(function()
    ar.Text = "weapon is currently unavailable"
    ar.Active = false
    cb.Text = "weapon is currently unavailable"
    cb.Active = false
    gl.Text = "weapon is currently unavailable"
    gl.Active = false
    pistol.Text = "weapon is currently unavailable"
    pistol.Active = false
    rl.Text = "weapon is currently unavailable"
    rl.Active = false
    smg.Text = "weapon is currently unavailable"
    smg.Active = false
    shotgun.Text = "weapon is currently unavailable"
    shotgun.Active = false
    sniper.Text = "weapon is currently unavailable"
    sniper.Active = false
    turnFoward.Text = "this button is currently unavailable"
    turnFoward.Active = false
    turnBack.Text = "this button is currently unavailable"
    turnBack.Active = false
    wait(300)
    ar.Text = "Assault Rifle"
    ar.Active = true
    cb.Text = "Crossbow"
    cb.Active = true
    gl.Text = "Grendade Launcher"
    gl.Active = true
    pistol.Text = "Pistol"
    pistol.Active = true
    rl.Text = "Rocket Launcher"
    rl.Active = true
    smg.Text = "SMG"
    smg.Active = true
    shotgun.Text = "Shotgun"
    shotgun.Active = true
    sniper.Text = "Sniper"
    sniper.Active = true
    turnFoward.Text = "Turn Forward"
    turnFoward.Active = true
    turnBack.Text = "Turn Back"
    turnBack.Active = true
end)