"Attempt to call a UDim2 value" when trying to tween a gui?

I have a GUI that I want to tween when a button is clicked, and I'm pretty sure I wrote it correctly because I compared it to another working tween script I have.

button.MouseButton1Up:Connect(function()
	if not selected then
		InventoryFrame:TweenPosition(
			UDim2.new(0.499, 0, 0.063, 0)
			"Out",
			"Quad",
			1,
			true
		)
		selected = true
	else
		InventoryFrame:TweenPosition(
			UDim2.new(1.2, 0, 0.063, 0),
			"Out",
			"Quad",
			1,
			true
		)
		selected = false
	end
end)

When I click the button I get an output saying Players.frogeater12345.PlayerGui.Hotbar.Hotbar.Inventory5.InventoryButtonScript:9: attempt to call a UDim2 value

Try this, instead of doing "if not selected then", try to remove those parts and don't do the else statement because it is like saying if I pressed it then the GUI stays the same or something like that, just make sure the GUI is off of the screen before you press the button the open the GUI.

For example, this is what I did for one of my GUI's:

local QuoteButton = script.Parent.MainMenu.QuoteoftheMonthButton
local quote = script.Parent.QuoteoftheMonth
local Exit = script.Parent.QuoteoftheMonth.ExitButton

QuoteButton.MouseButton1Click:Connect(function()
	local mouse = game.Players.LocalPlayer:GetMouse()
	script.Parent.Parent.Click:Play(mouse)
	quote:TweenPosition(
		UDim2.new(0.296, 0,0.103, 0),
		"Out",
		"Quart",
		1,
		false,
		nil
	)
end)

Exit.MouseButton1Click:Connect(function()
	local mouse = game.Players.LocalPlayer:GetMouse()
	script.Parent.Parent.Click:Play(mouse)
	quote:TweenPosition(
		UDim2.new(0.296, 0,-1, 0),
		"Out",
		"Quart",
		1,
		false,
		nil
	)
end)