After i activated my account when i pre-ordered the game, i promptly threw away the code. Unaware that i needed the code again. And now i do to log in and set up my subscription. WHAT DO I DO?
I doubt you need a code that you already entered once. More likely, you entered a preorder code that granted you early access, and now you need a full game code(which is different) to set up a subscription plan.
You should get the full game code from the retailer that sold you the game.