I don't think that's your fault Marcus. The author sets the story to listed or unlisted. It's their choice. You cannot change it, as far as I know. If she set it to unlisted before sending it to you, that's her choice - or her mistake, if it was a mistake. Some people prefer to have some of their work not behind the paywall, so I just let authors decide.

We all just need to check those tick boxes before we submit!