Thanks will do tomorrow. Don’t think it’s aluminum, but could be wrong. It did have a little damage before I purchased it 7 years ago. But I put marine silicone ( good luck separating it) to seal the possible crack.ABS is a type of material roofs, such as on Coleman popups, ere made from. It tends to crank, and/or delaminate. Yours sort of looks like a textured aluminum one.
You might want to look through this section and see if you find one thread that looks like your roof. https://www.popupportal.com/forums/roof-floor-repair-maintenance.53/
I'm still camping with funky internet so I can't give you too many links for the moment