UGG Brown Leather Fleece-Lined Mid Calf boots - marked as size 4 fits like 5.5

Brown Leather Fleece-Lined Mid Calf boots from UGG - marked as Women’s US size 4 but fits like a size US 5.5 though, so marked as this I usually wear a women’s 5.5 in most brands (example 5.5 in Sam Edelman and these fit) Happy to send additional measurements as well, just comment! :)