Script works in studio but not in game?

Here is my script. It works (almost) perfectly in studio, but doesn't work AT ALL in game. Why?

EDIT: Now the script doesn't work in Studio either. Whoop-de-doo. It used to work perfectly. I changed NOTHING

repeat
    wait()

game.Workspace.dungeon:Play()   

local hint = Instance.new('Hint', Workspace)
hint.Text = "Beginning the game.."
wait(20)
hint:Destroy()

game.Workspace.dungeon:Stop()


modelOfBricks = game.Workspace.spawnwalls
nameOfBricks = "spawnwall"

for i,v in pairs(modelOfBricks:GetChildren()) do
    if v.Name == nameOfBricks then
        v.Transparency = 1
        v.CanCollide=false
    end
end

game.Workspace.boss3:Play()

local hint = Instance.new('Hint', Workspace)
hint.Text = "Go go go!"
wait(4)
hint:Destroy()


game.Lighting.Venomshank:Clone().Parent = game.Workspace
game.Lighting.Darkheart:Clone().Parent = game.Workspace
game.Lighting.Illumina:Clone().Parent = game.Workspace

wait(180)
for i, player in ipairs(game.Players:GetPlayers()) do
    if player.Character then
        local hum = player.Character:FindFirstChild('Humanoid')
        if hum then
            hum.Health = 0
        end
    end
end

game.Workspace.boss3:Stop()

local stat = "KOs"
local players = game.Players:GetPlayers()

for i,v in pairs(players) do 
    if v.leaderstats then
        local lstat = v.leaderstats:FindFirstChild(stat)
        if lstat then
            lstat.Value = 0 
        end
    end
end

local hint = Instance.new('Hint', Workspace).
hint.Text = "The round has ended"
wait(4)
hint:Destroy()


modelOfBricks = game.Workspace.spawnwalls
nameOfBricks = "spawnwall"

for i,v in pairs(modelOfBricks:GetChildren()) do
    if v.Name == nameOfBricks then
        v.Transparency = 0
        v.CanCollide=true
    end
end

until 1+1==3