Teleporting Script doesn't work, yet the Output says 'It isn't a valid member' even though it is?

local player = game.Players.LocalPlayer
local char = player.Character

game.Workspace.Tardis.Door.Knob.ClickDetector.MouseClick:connect(function()
	for i = 1,0,-0.1 do
		player.PlayerGui.ScreenGui.Frame.BackgroundTransparency = i
		player.PlayerGui.ScreenGui.Frame.TextLabel.TextTransparency = i
		wait()
	end
	wait(1)
	char.HumanoidRootPart.CFrame = game.Workspace.TargetBlock.CFrame + Vector3.new(0,3,0)
	wait(1)
	for i = 0,1,0.1 do
		player.PlayerGui.ScreenGui.Frame.BackgroundTransparency = i
		player.PlayerGui.ScreenGui.Frame.TextLabel.TextTransparency = i
		wait()
	end
end)

The game itself has 'Filtering Enabled'. The script also works before, but now it doesn't work. I tried going to the output, but it suggested that, "Knob isn't a valid member of the model." It's weird because it's the actual name of the object yet it won't do the script. Is there something missing that I'm not aware of?

First, try using workspace alone. It's better also take a look at :MoveTo(), it's a better CFrame based teleportation method. Sometimes a Script can run faster than the Assets can load, try adding a delay or saying workspace.Tardis.Door:WaitForChild("Knob") to see if it rests at " "infinite yield possible", therefore It's best to take a harder look at why it's not recognizing it, maybe look at your spelling too