Table datastore attempt to call a nil value?

So, this is my datastore script so far, however for some reason, it's attempting to call a nil value. Here's my script:

local DS = game:GetService("DataStoreService"):GetDataStore("Inventories")
game.Players.PlayerAdded:Connect(function(player)
	variablePlayer = player.Name
    local folder = Instance.new("Folder",player)
    folder.Name = "inventory"
    inventory = {}
    inventory.Name = "inventory"
    local dataKey = "userkey_"..player.UserId
    local data
    local success,errormsg = pcall(function()
        data = DS:GetAsync(dataKey)
    end)
    if not success then
        warn("Error when retrieving data for "..player.Name..". Error: "..errormsg)
        folder.Value = nil
    end
    end)
game.Players.PlayerRemoving:Connect(function(player)
    local success,errormsg = pcall(function()
        for i, v in pairs(game.Players[variablePlayer].inventory:GetChildren()) do
			inventory.insert(v.Value) -- This is where the error is.
			print(v.Value)
        end
	DS:SetAsync("userkey_"..player.UserId, inventory)
    end)
    if not success then
        warn("Unable to save for "..player.Name..". Error: "..errormsg)
    end
end)

Error message:

Unable to save for 7z99. Error: ServerScriptService.inventory:21: attempt to call a nil value