Reiss Isla Cut Out Summer Dress, label says 4 but fits a 6

THE ISLA, IN AN EXPERTLY DESIGNED FLORAL PATTERN, FEATURES FEMININE DETAILS FOR AN EYE-CATCHING LOOK. THIS PIECE IS CRAFTED TO A MIDI LENGTH WITH A FITTED SILHOUETTE AND HAS DOUBLE SKINNY STRAPS AS WELL AS A CUT-OUT TO BOTH FRONT AND REVERSE, WITH A SELF-TIE DETAIL TO THE BACK OF THE DRESS. WEAR WITH SANDAL HEELS TO ALL OF YOUR UPCOMING WARM-WEATHER OCCASIONS.