Why Doesn't this recognize "PlayerGui" as a member of "Player"?

I'm trying to create a party request script but whenever i run the script. it says that "PlayerGui" isn't a member of "Player". if somebody can help i'd really appreciate it . Thx :D

Button = script.Parent

Button.MouseButton1Down:connect(function()
	local PName = script.Parent.Parent.PlayerName	
	local Player = game.Players[PName.Value]
	local You = game.Players.LocalPlayer
	script.Parent.Parent.Visible = false 
	if not Player.PlayerGui:FindFirstChild("Invite") then
		local gui = script.Invite:clone()
		gui.Parent = Player.PlayerGui
		gui.PlayerName.Value = PName.Value 
		gui.InviterName.Value = You.Name 
		gui.Frame.Visible = true 
		gui.Frame.lblText.Text = "Invite from ".. You.Name
	end	
end)

If your game is FilteringEnabled, you cannot access another player's PlayerGui locally through a LocalScript.

What I would recommend you to do is to keep up with parties (like who's in a party, maximum amount of people, etc.) with StringValue objects and other objects such as Folders and IntValues (or whatever else you for providing information of a party in a GUI) inside of Workspace.

You have to use RemoteFunctions and RemoteEvents (here's the wiki page) accordingly to talk to Workspace (such as when you want to add a person to a party when he/she clicks a specific GUI).

However, you DON'T need to use RemoteFunctions or RemoteEvents when you just want to read a value. For example, if you have a StringValue named "PlayerName" inside a party Folder called "Party1" in Workspace, you can just do this from the client to retrieve the player's name:

local name = game.Workspace.Party1.PlayerName.Value

Hope this helps!