OfflinePlayer player = Bukkit.getOfflinePlayer(namespace.replace("~", ""));
if(player.hasPlayedBefore()) {
String originalNamespace = namespace;
try {
ProfileService resolver = HttpRepositoryService.forMinecraft();
Profile profile = resolver.findByName("player.getName()"); // May be null
namespace = "~" + CraftBookPlugin.inst().getUUIDMappings().getCBID(profile.getUniqueId());
CopyManager.renameNamespace(CraftBookPlugin.inst().getDataFolder(), originalNamespace, namespace);
sign.setLine(0, namespace);
} catch (Exception e) {