Depending on their size, just remove them. Quite a few of the decals on my Sunline started cracking and peeling. I used a hair dryer and WD40 to remove them. Once removed, you have the option of replacing them if they are still available for the trailer which means you would probably have to contact the manufacturer to check if they are available.
2012 Newmar Bay Star 3302
Blue Ox Avail
BrakeBuddy Advantage
2015 Malibu
"Get busy living, or get busy dying."
Andy Dufresne, The Shawshank Redemption