You didnt lose any credits, so Im assuming someone outbid you. I logged in, but didnt see any sort of event one way or the other, so Im not sure how you even tell if you're winning or losing an auction :/
As others have implied, putting a bid on the NPC market is just that - a bid. It only ever shows you your bids, not everyone elses. SO in all likelihood someone else had bid an amount higher than yours and so they won the ship and paid the credits for it.