Sealing edges of trailer. What putty or caulking do you use?

Between the edge molding and the outside wall it seems they used some kind of black putty on my trailer. Some of it has came out with time. It doesn’t seem like caulking and more like a putty. What would you guys replace it with? My trailer is has outside fiberglass walls and metal edge trim. Looking to get something that is black like the trim since my trailer is grey with black trim.