Please Help me.

Hello, I searched and searched throughout the website and asked everyone I knew in game about this:
How do you switch Factions?
When I first started I was on the Kurzick side, then I joined a new guild and had to switch to Luxon.
Now I am creating a guild fresh out of the Luxon guild, and I know you have to visit the House zu Heltzer to change your guilds faction, but it will not let me in because I am Luxon.

How do I fix this?

If you have left your guild then I guess maybe you have to trade in all of your remaining Luxon faction before you can setup a Kurzick Guild?

i think you need to do this quest

http://gw.gamewikis.org/wiki/Befriending_the_Kurzicks