Go to the FL Studio website, and folow the intructions to log in, you should have gotten e-mails with user name and password, if you misplaced that, then at least get your user name, they will then search against their data base for it and send you a new reg. code, if not then you outta luck bruh! I've been using Frutiy Loops now FL Studio for years since its been out, so i know.
They are very strigint with piracy, so you need to go through the proper channels to get you reg code back.
Musiq