After buying item in shop leaderboard stats do not save and it all reverts and adds more?

So, we have a special currency system in our game and it all works fine, but when said amount of 10 points are subtracted it subtracts, but when the points automatically update within 5 seconds, it reverts back to the old amount and adds 5, how can it be stopped from reverting?

Link to GIF: https://gyazo.com/a3a7e58a86a16c449dea3c5708a327ef

MilesAdding Script:

--Config Scripts--

amount = 5

timedelay = 5

currencyname = "SkyMiles"

--Script--

while true do
	wait(timedelay)
	for i,v in pairs(game.Players:GetPlayers()) do
		if v:FindFirstChild("leaderstats") then
			v.leaderstats[currencyname].Value = v.leaderstats[currencyname].Value + amount
		end
	end
end

Leaderboard and Saving Script:

local dStore = game:GetService("DataStoreService"):GetDataStore("SkyFlySavingModule")

function createLeaderboard(plr)
	local ls = Instance.new("IntValue")
	ls.Name = "leaderstats"
	local pts = Instance.new("IntValue")
	pts.Parent = ls
	pts.Name = "SkyMiles"
	ls.Parent = plr
end

game.Players.PlayerAdded:Connect(function(plr)
	plr.CharacterAdded:connect(function(char)
		createLeaderboard(plr)
		local save = dStore:GetAsync(plr.UserId.."_SAVE")
		if save ~= nil then
			plr.leaderstats.SkyMiles.Value = save
		end
		
	end)
end)

game.Players.PlayerRemoving:Connect(function(plr)
	local saving = plr.leaderstats.SkyMiles.Value
	dStore:SetAsync(plr.UserId.."_SAVE",saving)
end)

game:BindToClose(function()
	wait(5)
end)

Shop Script:

local plr = game.Players.LocalPlayer

script.Parent.MouseButton1Click:Connect(function(click)
	if plr.leaderstats.SkyMiles.Value >= 10 then
		plr.leaderstats.SkyMiles.Value = plr.leaderstats.SkyMiles.Value - 10
		
		local PasswordGUI = script.Parent.Parent.TweenGUIPassword
		PasswordGUI:TweenPosition(UDim2.new(0.25,0,0.25,0),"Out","Elastic",1,true)
		
		local BuyTestUI = script.Parent.Parent.Parent.MainFrame
		BuyTestUI:TweenPosition(UDim2.new(2,0,0,0),"Out","Elastic",1,true)
	end
end)