White party dress

No size on tag, but measurements are as follows: waist: 15 in. pit to pit: 16.5 in. length (from top without straps to bottom hem): 34 in. Very elegant white dress with tulle straps and lined tulle skirt and gorgeous black embroidery and beads! Received as a gift but it’s too big on me :( I’m usually a size 6/8 in dresses, and this seems to fit like a larger 8 or 10.