First start checking for leaks on the roof and especially on awning trim.
I've been repairing such delamination on my Fleetwood.
Not having good press, it will show some imperfection, but will stay solid as I am using my camper 5 years after 1st repair.
Remove jack and all trims in this area and then pull the skin out. Inspect if that is just delamination, or rotten plywood under.
If just delamination, I used the most expensive "liquid nails" HD had and uses paint mixing spatula to push the glue into narrowing gap.
Than piece of thick plywood outside, or wide 2x stock with maze of ladders and sticks pushing it against the camper for at least 3 days.