My trailer is a 2011 Sonnybrook Harmony 21FBS. Overhead lights are dual fixture LED type with a slide switch. There are 3 lights of this type in the center of the trailers (others in there as well, ...
I would remove nearby fixtures and check for loose wires. They are daisy-chained from one to the next so your wiring fault could be at one of the others. You may even be able to give the wires a little tug and look for movement at the offending fixture. BTW, the 12V side is not referred to as hot and neutral - just pos. and neg, plus and minus, etc. :)