Spectate script makes camera freeze in place?

I followed a tutorial for how to make a spectating script from a video on Youtube made one year ago(video maker is TheIceZombieSlayer Videos). Everything works fine, except every so often when I enter my game the camera gets stuck in one place and I cannot move it, while the rest of my game runs like normal(resetting does not help). It doesn't seem like anyone in the comment section of the video had the same problem I am having. I will paste my code below:

Player = game.Players.LocalPlayer
ScGUI = script.Parent
Camera = game.workspace.CurrentCamera
UIS = game:GetService("UserInputService")

Spectating = false
Index = 1

Camera.CameraSubject = Player.Character

function Watch(player)
	if player and player.Character and Camera.CameraSubject ~= player.Character then
		Camera.CameraSubject = player.Character
		ScGUI.SpectateFrame.TextLabel.Text = "*"..player.Name.."*"
	end
end

function ChangeState(bool)
	if bool == nil then
		Spectating = not Spectating
	else
		Spectating = bool
	end
	
	if Spectating then
		ScGUI.SpectateButton.Image = "rbxassetid://3376963769"
		ScGUI.SpectateFrame.Visible = true
	else
		Watch(Player)
		ScGUI.SpectateButton.Image = "rbxassetid://3364442186"
		ScGUI.SpectateFrame.Visible = false
	end
end


function CurrentCourse()
	return workspace.CurrentCourse:GetChildren()[1]
end

function IncrementIndex(num)
	local TempIndex = Index + num
	local Course = CurrentCourse()
	local TempContestants = Course.CourseInfo.TempContestants
	local Contestants = TempContestants:GetChildren()
	
	if TempIndex > #Contestants then
		TempIndex = 1
	elseif TempIndex < 1 then
		TempIndex = #Contestants
	end
	Index = TempIndex
end

ScGUI.SpectateButton.MouseButton1Click:connect(function ()
	ChangeState()
end)


UIS.InputBegan:connect(function (Input)
	if Input.KeyCode == Enum.KeyCode.Q then
		IncrementIndex(-1)
	elseif Input.KeyCode == Enum.KeyCode.E then
		IncrementIndex(1)
	end
end)

ScGUI.SpectateFrame.PreviousButton.MouseButton1Click:connect(function ()
	IncrementIndex(-1)
end)
ScGUI.SpectateFrame.NextButton.MouseButton1Click:connect(function ()
	IncrementIndex(1)
end)


game:GetService("RunService").RenderStepped:connect(function ()
	local Course = CurrentCourse()
	if Course then
		local TempContestants = Course:WaitForChild("CourseInfo"):WaitForChild("TempContestants")
		local Contestants = TempContestants:GetChildren()
		
		if not TempContestants:FindFirstChild(Player.Name) then
			ScGUI.SpectateButton.Visible = true
			if Spectating then
				IncrementIndex(0)
				Watch(Contestants[Index].Value)
			end
		else
			ScGUI.SpectateButton.Visible = false
			ChangeState(false)
		end
	else
		ScGUI.SpectateButton.Visible = false
		ChangeState(false)
	end
end)

Can someone please explain how I can fix this glitch?