Here’s what consumers have asked with answers from Etsy staff and previous consumers.
Etsy isn't one seller, it's various people opening up shops to sell their stuff. You need to contact which seller(s) on the website you might want to buy from and work something out. I wouldn't buy your dresses from strangers on the Internet. Just go to a real store.
Etsy cannot give you any information about a seller. Each seller has their own shop, policies, and is not controlled by anyone, though there are policies and terms of service for each shop to follow in using the website. They are simply using the website to sell their product. In order to check reputation, look at the shop owners feedback. Ask questions. See how long they have been opened for business, then be sure to read their policies regarding loss, replacement, returns, etc. Stay away from those that say No returns allowed. That's a bad policy, as a buyer should have recourse if they are unhappy or something is lost/damaged.
You would contact that individual shop owner where it says on their front page "Contact Shop Owner". Each shop has their own policies so it's good to read them. Explain the situation and ask for their return shipping address. You most likely will have to pay to cover the postage which is expected anywhere online.
I am thinking you should never build your business in Etsy. There is no guaranty you be there tomorrow, They shut your business, you will lose all and if you have any money in credit or you have any sale on process all be gone surprisingly. No customer service no manor no respect. They talk about craft but they lie. Tell me sewing thread is handmade? Or sex toys is handmade? But they told me Persian carpet hand knotted, work of 6 Months is not handmade they closed my business they owe me money I had sell on process and no one there to respond my Question. I would recommend not to be there.
If you go to the seller's site on Esty.com, you will see in the lower right corner of their site a communication box you can type comments or questions into. As with all of Esty.com seller's site, you should look at the entire seller's site before going outside of Esty.com for help. It saves you, Site Jabber and Esty.com wasted time.