My game script plays a few rounds, suddenly errors, and stops?

Hi, this is an irritating error. I finished my gamescript, plays all rounds and stuff. However, after a couple of rounds, it errors with this:

"ServerScriptService.Game:31: attempt to index global 'typeName' (a nil value)"

And the script stop working.

I have no idea how to fix this, its driving me crazy!!

status = game.ServerScriptService.Status
local type = {"Meteor Shower","Raining Noobs","Moon","Eerie Darkseed","Tsunami","Master Hand","Acid Rain","Deadly Egg Rain","Rising Lava","Epic Duck","Raining Knives","Shoop Da Whoop"}
sfx = {}
map = {}
leaderboard = nil
local w = game.Workspace:getChildren()
for i=1,#w do
	if w[i].Name == "leaderboard" and w[i]:findFirstChild("running") ~= nil and w[i]:findFirstChild("points") ~= nil then
		leaderboard = w[i]
	end
end

for i,game in pairs (game.ServerStorage:FindFirstChild("Maps"):GetChildren()) do
	table.insert(map,#map+1,game.Name)
end

for i,game in pairs (game.ServerStorage:FindFirstChild("SoundTrack"):GetChildren()) do
	table.insert(sfx,#sfx+1,game.Name)
end

while true do
	print(#map)
	mapName = map[math.random(1, #map)]
	mapName = game.ServerStorage.Maps:FindFirstChild(mapName)
	mapClone = mapName:Clone()
	mapClone.Parent = game.Workspace
	mapClone:MakeJoints()
	print (#type)
	typeName = type[math.random(1, #type)]
	typeName = game.ServerStorage.enemies:FindFirstChild(typeName)
	typeClone = typeName:Clone()	
	game.Workspace.Lobby:Play()
	for i = 60, 1, -1 do
		status.Value = "Round 1/5 will start in: "..i
		wait(1)
	end
	game.Workspace.Lobby:stop()
	status.Value = "Disaster: "..typeClone.Name
	wait(3)	
	sfxName = sfx[math.random(1, #sfx)]
	sfxName = game.ServerStorage.SoundTrack:FindFirstChild(sfxName)
	sfxClone = sfxName:Clone()	
	sfxClone.Parent = game.Workspace
	sfxClone:play()
	workspace.points.Value = 20
	game.Workspace.running.Value = true
	typeClone.Parent = game.Workspace
	typeClone:MakeJoints()
	for i = 30, 1, -1 do
		status.Value = "Time until round ends: "..i
		wait(1)
	end
	typeClone:remove()
	sfxClone:Stop()
	sfxClone:destroy()		
	game.Workspace.running.Value = false
	status.Value = "Results!"
	wait(5)
	print (#type)
	typeName = type[math.random(1, #type)]
	typeName = game.ServerStorage.enemies:FindFirstChild(typeName)
	typeClone = typeName:Clone()	
	game.Workspace.Lobby:Play()
	for i = 15, 1, -1 do
		status.Value = "Round 2/5 will start in: "..i
		wait(1)
	end
	game.Workspace.Lobby:stop()
	status.Value = "Disaster: "..typeClone.Name
	wait(3)	
	sfxName = sfx[math.random(1, #sfx)]
	sfxName = game.ServerStorage.SoundTrack:FindFirstChild(sfxName)
	sfxClone = sfxName:Clone()	
	sfxClone.Parent = game.Workspace
	sfxClone:play()
	workspace.points.Value = 20
	game.Workspace.running.Value = true
	typeClone.Parent = game.Workspace
	typeClone:MakeJoints()
	for i = 30, 1, -1 do
		status.Value = "Time until round ends: "..i
		wait(1)
	end
	typeClone:remove()
	sfxClone:Stop()
	sfxClone:destroy()		
	game.Workspace.running.Value = false
	status.Value = "Results!"
	wait(5)
	print (#type)
	typeName = type[math.random(1, #type)]
	typeName = game.ServerStorage.enemies:FindFirstChild(typeName)
	typeClone = typeName:Clone()	
	game.Workspace.Lobby:Play()
	for i = 15, 1, -1 do
		status.Value = "Round 3/5 will start in: "..i
		wait(1)
	end
	game.Workspace.Lobby:stop()
	status.Value = "Disaster: "..typeClone.Name
	wait(3)	
	sfxName = sfx[math.random(1, #sfx)]
	sfxName = game.ServerStorage.SoundTrack:FindFirstChild(sfxName)
	sfxClone = sfxName:Clone()	
	sfxClone.Parent = game.Workspace
	sfxClone:play()
	workspace.points.Value = 20
	game.Workspace.running.Value = true
	typeClone.Parent = game.Workspace
	typeClone:MakeJoints()
	for i = 30, 1, -1 do
		status.Value = "Time until round ends: "..i
		wait(1)
	end
	typeClone:remove()
	sfxClone:Stop()
	sfxClone:destroy()		
	game.Workspace.running.Value = false
	status.Value = "Results!"
	wait(5)
	print (#type)
	typeName = type[math.random(1, #type)]
	typeName = game.ServerStorage.enemies:FindFirstChild(typeName)
	typeClone = typeName:Clone()	
	game.Workspace.Lobby:Play()
	for i = 15, 1, -1 do
		status.Value = "Round 4/5 will start in: "..i
		wait(1)
	end
	game.Workspace.Lobby:stop()
	status.Value = "Disaster: "..typeClone.Name
	wait(3)	
	sfxName = sfx[math.random(1, #sfx)]
	sfxName = game.ServerStorage.SoundTrack:FindFirstChild(sfxName)
	sfxClone = sfxName:Clone()	
	sfxClone.Parent = game.Workspace
	sfxClone:play()
	workspace.points.Value = 20
	game.Workspace.running.Value = true
	typeClone.Parent = game.Workspace
	typeClone:MakeJoints()
	for i = 30, 1, -1 do
		status.Value = "Time until round ends: "..i
		wait(1)
	end
	typeClone:remove()
	sfxClone:Stop()
	sfxClone:destroy()		
	game.Workspace.running.Value = false
	status.Value = "Results!"
	wait(5)
	print (#type)
	typeName = type[math.random(1, #type)]
	typeName = game.ServerStorage.enemies:FindFirstChild(typeName)
	typeClone = typeName:Clone()	
	game.Workspace.Lobby:Play()
	for i = 15, 1, -1 do
		status.Value = "Round 5/5 will start in: "..i
		wait(1)
	end
	game.Workspace.Lobby:stop()
	status.Value = "Disaster: "..typeClone.Name
	wait(3)	
	sfxName = sfx[math.random(1, #sfx)]
	sfxName = game.ServerStorage.SoundTrack:FindFirstChild(sfxName)
	sfxClone = sfxName:Clone()	
	sfxClone.Parent = game.Workspace
	sfxClone:play()
	workspace.points.Value = 20
	game.Workspace.running.Value = true
	typeClone.Parent = game.Workspace
	typeClone:MakeJoints()
	for i = 30, 1, -1 do
		status.Value = "Time until round ends: "..i
		wait(1)
	end
	typeClone:remove()
	sfxClone:Stop()
	sfxClone:destroy()		
	game.Workspace.running.Value = false
	status.Value = "Results!"
	wait(5)
	mapClone:Destroy()
end