Roof's Rear Crossbar Doesn't Lock In The Last Hole

[yl1826]

There are two adjustable crossbars on the roof. On either ends of the crossbars there is a lever that can be pulled to "release" the crossbar from it's hole allowing you to move it forwards and backwards into a different hole along the rails. The front crossbar locks all the way into the very first hole (towards the front of the car). However the rear crossbar doesn't seem to lock into the very last hole (rear of the car).

Is this even a problem or is the rear crossbar not supposed to lock into the very edge.

I might need to take pictures to describe what I mean.