I've also not yet received my Registration code. I received the email stating, "Endwalker registration code is now available!". But when I go to the "unlock your registration code" link, which directs me to my Endwalker order page on the Square Enix store, the only access code listed under my Endwalker purchase is the early access key. It's just the one key showing, there is no other code. So, yeah.. no registration code appears to have been provided to me. I've reached out to SE support this morning once I realized this, no word back yet. I'll report back if there is any progress.