DataStores Problem it wont work at all.. Why wont this Work?

i dont have a clue what is wrong here at all!!!

ive been trying for ages ;(

data = game:GetService("DataStoreService")
save = data:GetDataStore("Tools")


game.Players.PlayerAdded:connect(function(player)
    k = player.Backpack:WaitForChild("BDtest")
    k.Value = save:GetAsync(player.UserId) or 0
    save:SetAsync(player.UserId, k.Value)
    game.Players:WaitForChild(player)
    k.Changed:connect(function()
        save:SetAsync(player.UserId, k.Value)
    end)
    if k.Value == 1 then
        game.ReplicatedStorage.vamp["Blood Drain"]:Clone().Parent = player:WaitForChild("Backpack")
        player.Backpack["Stone Mask"]:Destroy()
        save:SetAsync(player.UserId, k.Value)
    end
end)



game.Players.PlayerRemoving:connect(function(player)
    local k = player.Backpack:WaitForChild("BDtest")    
    save:SetAsync(player.UserId, k.Value)
    if k.Value == 1 then
        save:SetAsync(player.UserId, k.Value)
    end
end)