Solved Itemstacks disappearing from inventory

This is driving me mad.

I have an inventory GUI that refuses to behave.

Code:

Inventory iv = Bukkit.createInventory(null, 36, ChatColor.LIGHT_PURPLE + pluginPrefix);

        ListFile file = new ListFile("plugins" + File.separator + "CommandsForSale" + File.separator + "Players"
                + File.separator + player.getUniqueId().toString(), "txt");
        ArrayList<String> bought = file.read();
        int pos = 1;
        FileConfiguration config = main.getConfig();
        for (ItemStack is: buyableCmds) {
            // lores of 5 is the command name
            String rawLore = is.getItemMeta().getLore().get(0);
            String [] lores = rawLore.split(" ");
            System.out.println("LORE NAME: " + lores[5]);
            if(!bought.contains(lores[5].toLowerCase())){
                System.out.println("HAS NOT BOUGHT: " + lores[5]);
                String perm = config.getString("CommandOptions."+ lores[5] + ".permission");
                if ((perm.equalsIgnoreCase("void") || player.hasPermission(perm))) {
                    System.out.println("HAS PERM: " + lores[5]);
                    System.out.println(iv.addItem(is));
                    pos++;
                }
            }
            if(pos == 36) {
                iv.addItem(overflowIcon);
                break;
            }
        }//end of loop through icons
        for(ItemStack is: iv.getContents())
            if(is != null) {
                System.out.println(is.toString());
            }
        System.out.println("Done");
        return iv;

Now when you see the console output, 2 ItemStacks were put into the inventory. They never make it in and they are not returned by Bukkit, meaning they were accepted. (Sorry about the picture. Appearently I can't copy the console. Don't ask me why)

Does anyone see something I don't?



Solved. ItemStack materials are determined by user, but I also included materials not valid in an inventory.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.