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