Antaina Shoes! New, never worn!

Bought these shoes and they don't fit. They've only been tried on. The box they arrived in is beat up, but the shoes are in perfect condition. They come with two matching laces to tie up the leg.
Europe Size - 40. But fits more like a US 9.5, maybe up to US 10
Color - White Glossy
Heel - 8cm Heel, 6cm Platform