The BH has re-pressurized. This can happen to the FEL or any other hydraulically actuated implement. It happens either because the pressure wasn't completely relieved before the BH was disconnected or just simply because of some atmospheric phenomanon /forums/images/graemlins/shocked.gif /forums/images/graemlins/tongue.gif /forums/images/graemlins/grin.gif, in any case the pressure needs to be relieved before the quick connects will couple.
The easiest way to do it is to use a 3/8ths socket extension and a rag.
Take the blunt end of the extension that normally inserts into a socket and insert it into the female coupling. Take the rag and cover the extension and coupling then depress the extension into the coupling. You should hear the pressure release. Sometimes it takes a good push and others it doesn't take much to push the release valve in. The rag is to keep the fluid from squirting into your eyes and onto your clothes.
Good luck
Volfandt