Trailer Brakes Disconnected message

Sorry was away for a bit. We did get things sorted out eventually. We tested things one more time on the trailer and found no faults. I ended up taking the truck back to the dealer a second time and they went through the wire harness with dielectric grease on all the connections but said they found no issues. Well, I ended up going back to the storage facility where I keep the trailer and was set on making a day out of it trouble shooting what I could on my own but when I connected it up everything worked as it should. My guess is something was not quite connected on the truck and the dealer fixed it and didn’t know it or just dumb luck. Either way I have tested it several times afterwards and seems fine now.