If after you've done what Kenny said to do and it still won't work, you may have to destroy the connector to get it off !! It was about 4 years before I went to remove my loader for the first time and all 4 of mine were corroded bad enough that I had to destroy them and buy new ones. You can bet I doped them up good with antiseize when I installed the new ones. Pull back on the sleeve and coat the balls and all contact points really good with it and work it back & forth a few times before reconnecting a hose to it. I also put some on the male end in the groove where the balls engage but was careful not to get it on the portion that slips into the "O"ring in the female side. Hopefully your problem is just the pressure build-up. Also note that warmer air temps and/or direct sun will build pressure in a disconnected hose - sometimes you have to release this pressure before you try to reconnect the hose or it won't go. I usually wrap the hose end with a rag and bump the tit with a piece of wood or rubber hammer to release the pressure.