Gui button to save values in data store not working?

So ive gotten it to save when you click a block so then I tried it with a gui button and it seems to not even run the full script. Much help appreciated.

local DataStoreService = game:GetService("DataStoreService")
local myDataStore = DataStoreService:GetDataStore("myDataStore")

script.Parent.MouseButton1Click:Connect(function(click)
	game.Players.PlayerRemoving:Connect(function(player)
		local success, errormessage = pcall(function()
			myDataStore:SetAsync(player.UserId.."-points",player.leaderstats.Points.Value)
		end)
		if success then
			print("Saved!!")
		else
			print("Something is not right!!!")
			warn(errormessage)
		end
	end)

First thing, DataStore Service is only for ServerScripts and LocalScripts. Also, there is no use for using Gui Buttons for saving Data. You can simple create a ServerScript, put it in ServerScriptService. Code : [The one from your code]

local DataStoreService = game:GetService("DataStoreService")
local myDataStore = DataStoreService:GetDataStore("myDataStore")

game.Players.PlayerRemoving:Connect(function(player)
        local success, errormessage = pcall(function()
            myDataStore:SetAsync(player.UserId.."-points",player.leaderstats.Points.Value)
        end)
        if success then
            print("Saved!!")
        else
            print("Something is not right!!!")
            warn(errormessage)
        end
end)

Lemme know if it helps!