If I may. Look at what others have said. make sure the ejector rod is tight. Clean behine the ejection star. Also make sure the cylinder lock pin and spring are moving freely. The is the rounded pin in the middle of the star. Open the cylinder and you should be able to push the pin in with your thumb until flush with the cylinder driver hub. In normal operation the release should push the pin in almost all the way. With the end of the pin rounded pushing the cylinder out should push it back the rest of the way.
To service and clean the cylinder and crane. Remove the screw above the trigger with the cylinder closed. Make sure you use a proper screw driver and be careful with the screw it has a spring and set point on it. Once that screw is out you open the cylinder, pull the crane out and it separates from the cylinder. This will allow you to clean up the cylinder and the crane. And allow easy inspection.