Givenchy leather sneakers

Size 40 givenchy white leather sneakers. I usually take a 8.5-9 and these slipped off my feet. I would think they would fit a 9-9.5.Wasn’t aware of how big they were, but kept them anyway. They have marks as shown. Still tons of life left! Worn a handful of times last year. Have been sitting ever since. Clean inside , no odors. No box .