Strapless Silk Dress in Light Blue from JCrew (6 petite)

This dress is exquisite and I would keep it but it doesn’t fit. It has hidden side pockets and can be dressed up or dressed down. It was worn twice I believe. The dress is discounted (I bought it on clearance as a final sale) because there are two small marks on the back of the dress near the bottom. The marks are from mud that kicked up from my heels on a rainy night. A photo of the area is included.