Kitchen sink hot water line came disconnected

Pcaprio

Member
While de-winterizing our Heartland Pioneer TB-27, the hot water line came disconnected from the hook-up under the sink.
I un-threaded the connecter and attempted to hook it back up.
However it now has a slow drip at the connecter and plastic elbow.
i noticed on the plastic elbow that connects to the hot water line, that there is a ring/lip on the top . Is that ring supposed to go inside the threaded connector or stay on the outside?
how do i repair/fix this?
 
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