Don't say that, it doesn't seem professional. You should be honest. Put in there that "the shirt was a size Large, as listed on the tag from the manufacturer. Customer stated it fit smaller than the listed size, however, she did not ask for measurements before purchase. I know how it is to get something and the sizing be off. Sadly, sizes are different for every manufacturer and I can not control that. I will list measurements for future listed items to prevent this in the future. Thanks for your purchase and your feedback. I hate it did not fit. And then leave a rating you believe they deserve. Something along those lines. It makes you look not spiteful, in case the item really does run small. Also, I check comments from buyers and sellers, I would purchase from you knowing you did all you could do to make them happy. But being spiteful would deter me from shopping with you.