Loop doesn't work in a loading script?

The 2 for loops that load "BoxData" and "UnitData" don't work, it prints G and H but it doesn't print anything in the 2 loops why??

local KillsData = game:GetService("DataStoreService"):GetDataStore("test16Kills") 
local MoneyData = game:GetService("DataStoreService"):GetDataStore("test16Money") 
local UnitData = game:GetService("DataStoreService"):GetDataStore("test16Units") 
local BoxData = game:GetService("DataStoreService"):GetDataStore("test16Units") 
local HasPlayed = game:GetService("DataStoreService"):GetDataStore("test16Played") 

game.Players.PlayerAdded:connect(function(plrjoining)
    wait(0.05)
    local success, message = pcall(function()
        local PlayerKey = "user_"..plrjoining.userId
        local plrnew = false
        if HasPlayed:GetAsync(PlayerKey) == nil then
            print(plrjoining.Name.." is a new player!")
            plrnew = true
            local PlayerKey = "user_"..plrjoining.userId
            HasPlayed:SetAsync(PlayerKey, true)
        end
        local PlayerKey = "user_"..plrjoining.userId
        local data = game.ServerStorage.savefolder:Clone()
        data.Name = plrjoining.Name
        if plrnew == false then
            data.Kills.Value = KillsData:GetAsync(PlayerKey)
            data.Money.Value = MoneyData:GetAsync(PlayerKey)
            local units = UnitData:GetAsync(PlayerKey)
            print"G"
            for number, unit in pairs (units) do
                print"Q"
                local value = Instance.new("StringValue")
                value.Name = unit
                value.Value = unit
                value.Parent = data.Units
                print"W"
            end
            print"H"
            local boxes = BoxData:GetAsync(PlayerKey)
            for number2, box in pairs (boxes) do
                print"A"
                local value = Instance.new("StringValue")
                value.Name = box
                value.Value = box
                value.Parent = data.Boxes
                print"S"
            end
        elseif plrnew == true then
            data.Kills.Value = 0
            data.Money.Value = 0
            local units = {"Gun AI", "Tank AI"}
            for number, unit in pairs (units) do
                local value = Instance.new("StringValue")
                value.Name = unit
                value.Value = unit
                value.Parent = data.Units
            end
            local boxes = {"Box #1"}
            for number2, box in pairs (boxes) do
                local value = Instance.new("StringValue")
                value.Name = box
                value.Value = box
                value.Parent = data.Boxes
            end
        end
        data.Parent = game.ServerStorage.SAVEDDATA
    end)
    if not success then
        print("An error occurred with loading "..plrjoining.Name.."'s data: "..message)
    end
end)