My item lister

What it is supposed to do is let you input a players name and it will give you a list of all the items in thier inventory, it works in a local script in roblox studio(you have to replace ScreenGui.Parent = game.CoreGui with the gui location of your character for a local script) but it dosn't work in script  executers(here is the code I have). anyone know what is wrong with it?

Draggable = False-- True = Draggable | False = Not draggable
game:GetService("StarterGui"):SetCore("SendNotification", {
    Title = "Item checker";
    Text  = "Note: WIP";
    Icon = "rbxassetid://936721732";
    Duration = math.random(4,6);
    Button1 = "Okay"
})
-- Objects
local ScreenGui = Instance.new("ScreenGui")
local Frame = Instance.new("Frame")
local PlaySubmit = Instance.new("TextButton")
local AudioID = Instance.new("TextBox")
local MusicPlayer = Instance.new("TextLabel")
local MusicPlayer_2 = Instance.new("TextLabel")
local Output = Instance.new("TextButton")
-- Properties
ScreenGui.Parent = game.CoreGui
Frame.Parent = ScreenGui
Frame.BackgroundColor3 = Color3.new(0.105882, 0.164706, 0.207843)
Frame.Position = UDim2.new(0.00910931174, 0, 0.578864336, 0)
Frame.Size = UDim2.new(0, 182, 0, 249)
Frame.Active = Draggable
Frame.Draggable = Draggable
PlaySubmit.Name = "PlaySubmit"
PlaySubmit.Parent = Frame
PlaySubmit.BackgroundColor3 = Color3.new(0, 1, 0.0666667)
PlaySubmit.Position = UDim2.new(0.0405219793, 0, 0.333471209, 0)
PlaySubmit.Size = UDim2.new(0, 165, 0, 26)
PlaySubmit.Font = Enum.Font.ArialBold
PlaySubmit.Text = "Items?"
PlaySubmit.TextColor3 = Color3.new(0, 0, 0)
PlaySubmit.TextScaled = true
PlaySubmit.TextSize = 14
PlaySubmit.TextWrapped = true
AudioID.Name = "AudioID"
AudioID.Parent = Frame
AudioID.BackgroundColor3 = Color3.new(1, 1, 1)
AudioID.Position = UDim2.new(0.106456041, 0, 0.20366402, 0)
AudioID.Size = UDim2.new(0, 142, 0, 22)
AudioID.Font = Enum.Font.ArialBold
AudioID.Text = "Player Name"
AudioID.TextColor3 = Color3.new(0, 0, 0)
AudioID.TextScaled = true
AudioID.TextSize = 14
AudioID.TextWrapped = true
Output.Name = "Output"
Output.Parent = Frame
Output.BackgroundColor3 = Color3.new(1, 1, 1)
Output.Position = UDim2.new(0.106456041, 0, 0.462, 0)
Output.Size = UDim2.new(0, 142, 0, 22)
Output.Font = Enum.Font.ArialBold
Output.Text = "Output"
Output.TextColor3 = Color3.new(0, 0, 0)
Output.TextScaled = true
Output.TextSize = 14
Output.TextWrapped = true
MusicPlayer.Name = "Music Player"
MusicPlayer.Parent = Frame
MusicPlayer.BackgroundColor3 = Color3.new(1, 1, 1)
MusicPlayer.Size = UDim2.new(0, 182, 0, 36)
MusicPlayer.Font = Enum.Font.ArialBold
MusicPlayer.Text = "Item finder"
MusicPlayer.TextColor3 = Color3.new(0, 0, 0)
MusicPlayer.TextScaled = true
MusicPlayer.TextSize = 14
MusicPlayer.TextWrapped = true
PlaySubmit.MouseButton1Click:connect(function()
    Output.text = "works"
    local this2 = ""
    for i, v in pairs(game.Players:FindFirstChild(AudioID.text).Backpack:GetChildren()) do
        this2 = this2..","..v.Name
    end
    Output.Text = this2
end)