Spectate Gui Only Works in studio? Any help?

Works in studio great :D, However not in actual gameplay.

Here is the script:

cam = game.Workspace.CurrentCamera

local bar = script.Parent.Bar
local title = bar.Title
local prev = bar.Previous
local nex = bar.Next
local button = script.Parent.Button

function get()
	for _,v in pairs(game.Players:GetPlayers())do
		if v.Name == title.Text then
			return(_)
		end
	end
end


local debounce = false
button.MouseButton1Click:connect(function()
	if debounce == false then debounce = true
		bar:TweenPosition(UDim2.new(.1,0,0.77,0),"In","Linear",1,true)
		pcall(function()
				title.Text = game.Players:GetPlayerFromCharacter(cam.CameraSubject.Parent).Name
		end)
	elseif debounce == true then debounce = false
		pcall(function() cam.CameraSubject = game.Players.LocalPlayer.Character.Humanoid end)
			bar:TweenPosition(UDim2.new(-.3,0,0.77,0),"In","Linear",1,true)
		end
end)

prev.MouseButton1Click:connect(function()
	wait(.1)
	local players = game.Players:GetPlayers()
	local num = get()
	if not pcall(function() 
		cam.CameraSubject = players[num-1].Character.Humanoid
		end) then
		cam.CameraSubject = players[#players].Character.Humanoid
	end
pcall(function()
				title.Text = game.Players:GetPlayerFromCharacter(cam.CameraSubject.Parent).Name
		end)
end)

nex.MouseButton1Click:connect(function()
	wait(.1)
	local players = game.Players:GetPlayers()
	local num = get()
	if not pcall(function() 
		cam.CameraSubject = players[num+1].Character.Humanoid
		end) then
		cam.CameraSubject = players[1].Character.Humanoid
	end
pcall(function()
				title.Text = game.Players:GetPlayerFromCharacter(cam.CameraSubject.Parent).Name
		end)
end)

You must use a LocalScript to execute the code on the camera. A normal script can be used for the rest of the code, but it is impossible to manipulate the camera without using a LocalScript.

is your game in experimental mode? if it is go to settings in studio (while in that specific game) and turn it off.that might help note : go to HOME and you will find settings there.