Dancing Queen Black Strapless Sequin Mermaid Formal Prom Gown Dress

This formal is a show stopper! Worn once, and in good preloved condition. Some beading loose but not noticeable unless searching for it like i was. The black ribbon in the back is missing, there is a shawl in place of it now but it would definitely need something a tad smaller before wearing, super easy quick fix. Size xs but I think it could fit a tad bigger as well since it is an adjustable back. Please confirm fit with measurements posted.