Something like this happened on our trailer. There is another switch by the control
panel that can turn all the lights off or on at once. Maybe you have one for one side and one for the other. Our switch was located next to our outside light. Not familiar with your unit but that might be the problem.
2011 Jay Feather Select 28U
2007 Silverado Crewcab LT 6.0L
Happily married and father of
two university students.