Active character name changed itself

I used to play some 15 years ago as character Pureiggy. I had 3 other characters, Miniiggy, MyBaby, and Puriggy. I have recently started playing again and only activated Pureiggy, Miniiggy, and MyBaby. I did not reactivate the ID of Puriggy. When I recently logged in to play as Pureiggy, I was using the character that I always used years ago and everything was correct. A couple of days ago, I went to log in and noticed that they character that I had been recently playing with, their name changed to Puriggy and I an unable to play with that character anymore and the character that was Puriggy has changed it's name to Pureiggy, making it playable. The names of these 2 characters changed on their own. Can this be corrected?

This is most likely due to server merges, and when the server merge occured, your character had the same name as one that already existed on the merged server.

Right now the only way to change names is to create a character on another server with the same name, and when you transfer you'll be required to change it.

You can go on the support site and file a ticket, but the above is probably the only resolution.

This is not the correct place for account/tech support issues. You should file a ticket on the square enix support site. They will move this thread to "not a bug report," so if you'd like to discuss it further, you should use the technical support section. But this is definitely a square enix support thing.