Attempt to index nil with 'new' tweenservice roblox

So, im making a gui and i want to tween its position, but then i need to apply a Tween.Completed:Wait() in it, and this cant be done with :TweenPosition

But for some reason its giving a strange error saying: Attempt to index nil with ‘nil’
Can anyone help me fix that?

The Script

local tweenservice = game:GetService("RunService")
local MainTweener = tweenservice:Create(Frame, TweenInfo.new(0.25, Enum.EasingStyle.Back, Enum.EasingDirection.In), {Position = Udim2.new(0.006, 0, 0.829, 0)})
MainTweener:Play()
MainTweener.Completed:Wait()

TweenService, not RunService

UDim2, not Udim2

Ohhh, how did i miss those 2 things

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