Need My Content IDFollow

I just bought XI again from Amazon after being away for a couple of years & i'm trying to figure out where my content id is.

I have my POL ID id, SE ID, all of that it just says I have no content id when I try to play the game.

I've seen people say to go to Square Enix Account Management but when I do that & go to select services > FFXI > Option List > & then under Playonline ID options I click on purchase registration codes but when I do it says this: The selected registration codes cannot be purchased because they have already been registered..

It also says I still have 16 character slots available.

Any ideas?

Thankss