Looking for Opinions

One product, Ive been selling for atleast two years, is one of my better selling listings. Lately Ive been noticing more returns than usual the last 6 months, mostly complaining that the size is too big ( its a household product). In response I have updated my keywords/negative keywords), added high resolution photos with instructions and side by side comparisons, updated my listing, the size being stated multiple times. And now more than ever ive been noticing more and more returns complaining about the size being too big. Im not sure what else to do. Any insight is appreciated.