I believe that I have been hacked.
You need to create a support ticket and explain what has happened.
support.guildwars2.com
ArenaNet Communications Manager
I agree that you should contact Support by filing a ticket through the “Ask a Question” tab on that linked page. They will be able to assist you. For tips on what information to provide in a ticket, please read this post and provide as much as possible to expedite the ticket.
Gaile Gray
Communications Manager
Guild & Fansite Relations; In-Game Events
ArenaNet
Communications Manager
Guild & Fansite Relations; In-Game Events
ArenaNet