Halo 3 rank disappearing?

[???????]

I played halo for a while .... I worked my way up to captain grade II not too bad but when I went back on after a few months my rank dissapeared and I had to start over...

 

[Lauren 3]

They changed it up a bit.
You now rank up seperately for each type of game. You still have an overall rank (all your exp points combined) but now you get the added fun of leveling up your rank on each type of game.
If you go to your halo 3 details screen you will see all the experience points you have earned, as well as the # of exp points you earned for the game type you are playing.
I was rather upset when they did this, but oh well it's just a game right?