@Moon22 There's a difference between "placed" items, which are fine, and "dropped" items, which are what she's referring to. These are things like DIYs you might have dropped on the beach for visitors to pick up or items you've dropped outside (leaf shapes) because you've run out of storage for example. I think fallen branches might also count. Tidy all these up and she'll be happy.
The star rating of the island is updated in real time so go and ask her about evals straight away after tidying and see what she says.