I'm afraid I don't have a good solution for you. You will just have to watch the spots and make sure it doesn't peel any more. What is peeling, graphics on metal or fiberglass?
All I can say is try to take some sort of adhesive and reattach the peeling pieces. I've tried it on replacement logos that the original adhesive didn't hold, but never for repairs. If it were a whole logo that was coming off, I'd recommend a thin film of silicone, but I don't think it will work in your case. The adhesive should help some, but you will have to keep an eye on it. I'm surprised you're having trouble with a 2004 model. The only way that I've seen striping peel is if it was replaced at some point and the new was not installed properly. Sunline had excellent graphics people and apply the striping almost flawlessly. The reason I asked about where the striping is peeling is the metal siding had the striping applied when the metal was still flat, and then it was bent with the striping on it. When the striping was applied flat, it was almost perfect. The doors were done later, along with other details (like storage doors), and that could have been done on the coach out on the floor, and more dust could have been present. The storage doors couldn't have been done ahead of time since the same door was used on a few different models.
2007 T-286SR Cherry/Granola, #6236, original owner, current mileage: 9467.8 (as of 5/26/19)
1997 T-2653 Blue Denim, #5471
1979 12 1/2' MC, Beige & Avocado, #4639
Past Sunlines: '97 T-2653 #5089, '94 T-2251, '86 T-1550, '94 T-2363, '98 T-270SR