Nod23

Hey all. I just got my gun a few weeks ago and I was attempting to adjust my velocity on the bottom of the gun on the regulator (?). Soon after adjusting it for really low velocity I developed a serious leak in that area. I am not sure what the problem is, nor am I sure if there is supposed to be an o-ring down there to stop leaks. Any help would be great!

P.S. I didn't take the adjuster off of the gun at any time.