Our Britax Boulevard is about 1 1/2 yrs old. Lately I can't seem to get the harness to tighten if I loosen it. It just kind of pulls tighter and the releases when I'm pulling on the tightening strap if that makes sense. DH can get it a little tighter if he pulls at a certain ange (like back, toward her feet) which I can't seem to do. Anyone know why this would happen and how I can get it working? I thought this car seat was fantastic before this, but never had a problem tightening any of our other seats.