Formal party dress GOLD

Ordered online for my daughter's wedding. Size chart was inaccurate. Way too big. Never worn, just tried on. Built in cups at the chest Color is much more yellow gold than champagne as shown in the online photo. Material is silky, high quality, fully lined. Hits me right at the knee. For reference, I typically wear a size 8-10 or M/L I'm 5"11 This is listed as a size 16, but would best fit a 12/14. Zipper back closure Would make a fabulous Holiday dress or special event dress. Paid $120, would like to recoup at least $80.