Leak in drain pipe connection under slide-out
2013 Bay Star has a leak under the slide-out pantry where the black fitting connects with a brass connection. When the slide opens, I have water on the floor. After investigation, I see the brass fitting(connection) rotates when the slide moves in or out (not sure if its meant to do that?). I attached a photo showing the brass fitting with the connection to the PVC black pipe. The leak is where the PVC pipe threads mate up with the brass fitting. Any help with this issue is greatly appreciated.