Character Login Issues

Hello, good evening! I'm back playing after a long time. I started with a Free to Play account, but when I reached level 20, and just before that, when they told me I had to validate the account by entering a valid email address, when I entered it and clicked on the link in the email, I got an error telling me that the account was already validated or that there was no account with that email address (the account is from 2009!) I thought maybe it was because it was Free to Play, so I activated a subscription and nothing, same problem. 

Any solution? Thanks!