Back off the black locking ring, extend that end of of the hose so it is not collapsed and screw the end into the hose, you will see "threads" in the orange part that you screw into, once you have the hose all the way in tighten the black locking ring up to the orange part.
This same thing happened to me this past weekend with our brand new Rhino Flex hose so I got me some experience
. I had the same one before but guess it had been screwed all the way in when it was assembled in China because I did not have this issue before.
This time the assembly was lacking.