Altar'd state dress size large, fits more like a small to medium

Reposhing this item I purchased from @diyhunnies. I want to wear this so badly, it's beyond cute! I'm normally a medium to large in dresses (size 8-10 depending on fabric, etc.), so I figured this dress would be perfect and with some room. However, I cannot zip the back up. If you're small to medium this large will fit you perfectly. I'm honestly wondering if the L on the label was a mistake. But anyway, my loss your gain. Send offers my way!