Divot/ sunken spot on roof-what should I do?

[Sam Zawatsky]

I noticed this divot/sunken spot when I was in the roof blowing off leaves and moss . I tried to go into the attic to view this from the inside but I couldn’t tell what was going on because there was a lot of insulation and drywall from the high ceilings of the house in the way. What should I do ? I was thinking of contacting the roofing company that did the re-roof in 2010 or the homeowners insurance?