Forgotten Tales

I knew that the account ID and ingame name existed separately, but I did not know that the account ID was the name of the in game. Can I change my account ID?

For the forum? You could always create a new account if needed, or maybe just a signature with your character name if you wanted to do that.

No, I want to change my in-game ID.

You can't change your account name. See section 2 of the help menu.

http://ftmmorpg.dmgamestudio.com/help/

Create a new character instead and use the existing one for storage.