First never attach the cylinder onto the auger inside the house/garage especially if it is leaking.
Second did you soap it to make sure it's the regulator and not the hose.
Third if it is the regulator leaking you need a new one, no way around it. (Sorry, but call Jiffy customer service)
All it takes is a tiny piece of dirt or rust to wreck a regulator, and they are not rebuildable.