I was on the free trial and got up way early in the morning to create a character on Excalibur. After a couple of days I was finally able to create a character. I have been playing for a few days and decided to purchase the game. After purchasing the game, I went in and tried to create a new character on Excalibur but it was grayed out.

Why am I prevented from creating a new character on a server I already have a character on?