Royal blue High low formal dress - never worn! Size 9/10 from Macys

I bought this dress a few years back for a trip to Spain and never ended up wearing it. It has never been worn and is in perfect condition. This dress zips in the back, has adjustable straps, and the back does have a bit of a train. Im 5’7”, wear a C-cup, and a 9/10 fit me best (typically I’m a size 4-6 but felt the waist on this was a bit small).