Help Creating an NPC Dialogue System

[abstract sparrow]

Hi everyone, I started scripting yesterday so please excuse if I ask any noob questions or include more code than necessary.
I am trying to create an NPC dialogue system based off this video.
https://www.youtube.com/watch?v=EJC8Y7Qhaf0

I have a few issues, such as my NPC dialogue system not opening up and the DialougeGui staying on the screen. I checked for errors and I'm kinda stumped so any help would be appreciated. Please let me know if you need any other information.

Errors ingame: https://imgur.com/tWnQOwu

Scripts: (my code)

DialogueController: https://pastebin.com/b4XQXAJg

DialogueData: https://pastebin.com/p7hXksXm

DialogueServerHandler: https://pastebin.com/4WHP8Qjs

[craggy sphinx]

TweenService:Create(mainFrame, TWEEN_INFO, {Position = targetPos}):Play()

Try splitting play in another line

[abstract sparrow]

Tried it and I'm still having the same error. Am I doing anything wrong here?

local targetPos = UDim2.new(0.5, 0, 0.95, 0)
mainFrame.Position = UDim2.new(0.5, 0, 1.1, 0)
local tween = TweenService:Create(mainFrame, TWEEN_INFO, {Position = targetPos})
tween:Play()

[abstract sparrow]

Bump

[craggy sphinx]

line 99 it's tween.Completed not Tween:Completed

Sorry, I didn’t have time to review the script more carefully

[abstract sparrow]

thanks!! there were also some errors in DialogueData which i ended up fixing. thanks for your help and time