I assume you are referring to a message on the Remote Display inside the RW. If so, that means that something has happened to the cable that runs from the remote to the inverter it's self. Make sure it's fully seated at each end and if so, start tracing the cable to see if it's been damaged.
Michelle & Ann
2018 Chevy 3500HD Crew Cab High Country DRW, D/A, 2016 RW39MB, Dual ACs, Auto Level, Auto Sat Dish, Stack W/D, King Sleep #, 17.5" Sailuns w/Disc, MORryde IS & Pin, Comfort Ride Hitch, 5.5 Onan, Res Fridge & Induction Cook Top