Game Timer Text Not Changing despite making functions for It (?)

Hello Developers!

As the title says, I made this round system, the problem Is that the GUI text Isn't changing

local GameTimer = 180 ---How long the round should be
local IntermissionTimer = 25 --- How long Intermission should be
local StartUpTimer = 3 ---How long will the player get ready before the round starts
local GUIMadeHint = game:GetService("StarterGui").TimerAndMessages
local HintText = GUIMadeHint.Hint.HintText
local Maps = { ---All maps---
	game:GetService("ReplicatedStorage").Maps["Old SFOTH Map"]
}

local function GameProgress()
	StartUpTimer = 3
	HintText.Text = "ROUND STARTING IN "..StartUpTimer
	--[[
		local GetReadyText = Instance.new("Hint")
	GetReadyText.Parent = game:GetService("StarterGui").HintsAndMesages
	GetReadyText.Text = "ROUND STARTING IN "..StartUpTimer
	]]
	while StartUpTimer > 0 do
		wait(1)
		StartUpTimer -= 1
		HintText.Text = "ROUND STARTING IN "..StartUpTimer
	end
	GameTimer = 180
	HintText.Text = GameTimer.." Before round ends"
	--GetReadyText.Text = GameTimer.." Before round ends"
	while GameTimer > 0 do
		wait(1)
		GameTimer -= 1
		HintText.Text = GameTimer.." Before round ends"
	end
	--game:GetService("Debris"):AddItem(GetReadyText,0)
end

local function GameEnded()
	HintText.Text = "GAME OVER!"
	--[[
	local GameOverText = Instance.new("Hint")
	game:GetService("Debris"):AddItem(GameOverText,3)
	GameOverText.Parent = game:GetService("StarterGui").HintsAndMesages
	GameOverText.Text = "GAME OVER!"
	]]
	wait(5)
	local MapFolder = game.Workspace.CurrentMap:GetChildren()
	for _, Map in ipairs(MapFolder) do
		if Map:IsA("Model") then
			Map:Destroy()
		end
	end
end

local function Intermission()
	IntermissionTimer = 25
	HintText.Text = "Next round starting In "..IntermissionTimer
	--[[
	local IntermissionText = Instance.new("Hint")
	IntermissionText.Parent = game:GetService("StarterGui").HintsAndMesages
	IntermissionText.Text = "Next round starting In "..IntermissionTimer
	]]
	while IntermissionTimer > 0 do
		wait(1)
		IntermissionTimer -=1
		HintText.Text = "Next round starting In "..IntermissionTimer
	end
	--game:GetService("Debris"):AddItem(IntermissionText,0)
end

local function GameStarting()
	local SelectedMap = Maps[math.random(1,#Maps)]
	SelectedMap.Parent = game.Workspace.CurrentMap
	HintText.Text = "MAP CHOSEN: "..SelectedMap.Name
	--[[
	local MapChoosenText = Instance.new("Message")
	MapChoosenText.Parent = game:GetService("StarterGui").HintsAndMesages
	MapChoosenText.Text = "MAP CHOOSEN: "..SelectedMap.Name
	]]
	wait(3)
	--game:GetService("Debris"):AddItem(MapChoosenText,0)
end

while true do
	GameEnded()
	Intermission()
	GameStarting()
	GameProgress()
end