Money Duplicating + .Changed not working?

(1) Problem: Datastore leaderboard duplicates money when a player joins and leaves quickly What I am trying to accomplish: A solution to the problem above ^

Script:

local datastore = game:GetService("DataStoreService")
local ds2 = datastore:GetDataStore("BankSaveSystem")

game.Players.PlayerAdded:connect(function(plr)

 local folder = Instance.new("Folder", plr)
 folder.Name = "stats"

 local wallet = Instance.new("IntValue", folder)
 wallet.Name = "Wallet"

 local bank = Instance.new("IntValue", folder)
 bank.Name = "Bank"

 wallet.Value = 0

 bank.Value = ds2:GetAsync(plr.UserId) or 0
 ds2:SetAsync(plr.UserId, bank.Value)

 bank.Changed:connect(function()
  wait(0.5)
  ds2:SetAsync(plr.UserId, bank.Value)
 end)

end)

(2) Problem: ".Changed" Event is not working with Number/IntValue What I want: For it to actually work and update the text.

game.Players.LocalPlayer.stats.Bank.Changed:Connect(function()
    script.Parent.BankAmount.Text = fBank
dddddddd
game.Players.LocalPlayer.stats.Wallet.Changed:connect(function()
    script.Parent.WalletAmount.Text = fWallet
end)

AND this doesn't work either

game.Players.LocalPlayer.stats.Bank.Value.Changed:Connect(function()
    script.Parent.BankAmount.Text = fBank
end)

game.Players.LocalPlayer.stats.Wallet.Value.Changed:connect(function()
    script.Parent.WalletAmount.Text = fWallet
end)