I'm having the exact same issue, and it started Wednesday night. I was on the Lodestone and found I was unable to edit any of my blogs, so I logged out and logged back in, to find an error saying I had no characters created on this account.

I went to the launcher and it gave me the "Suspicious activity, suspended login access" error, so I dealt with that by changing my password. I tried the launcher again and it now asks me to either create a new account, or register a current account.

I try to register my current account (AGAIN) with the registration code I have but it doesn't work. It says It's already in use. I've used my EA code and my launch code, and both of them are "in use".

I've been waiting going on to a week now to get a response from SE. I've been waiting 3 weeks for a response to an issue I had back in P4. So far, NOTHING besides auto-replies out the f--king Yin Yang