New fridge delivered today. Existing tubing too short to reach. Okay, go by package of new tubing with INCLUDES brass fittings such as compression nut, pin insert, etc. But the pin will not stay in the tube!!! I assemble as directed, -- Tube thru compression nut, pin into tube, screw the whole thing on the fridge (or the other end which is currently a connector between the too-short existing hose and the new hose) -- but then I can pull the hose right off. There's nothing keeping it on the pin while it's inside the compression nut. What gives? I'd suggest wrong size hose or pin, but it all came in the same package!! I refuse to believe I need to call a plumber for this. What's the answer?? Please please!