How do I increment tween my gui, it won't let me....??

Alright sooooo I have a custom chat! I want to tween every single text label by UDim2.new(0,0,0.01,0) but........... It won't let me.... It stays at UDim2.new(0,0,0,0), I tried almost everything to fix it, but it just stayed at 0,0,0,0 I need help...

items is the folder where a ton of textlabels are stored...

Here is my code:

for _, i in pairs(items) do
	if i.ClassName == "TextLabel" then
		i:TweenPosition(i.Position-UDim2.new(0,0,0.01,0))
	end
end

for _, i in pairs(items) do
	if i.ClassName == "TextLabel" then
		local a = i.Position
		a = a - UDim2.new(0,0,0.01,0)
		i:TweenPosition(a)
	end
end

Any help would be great