One return request later, I learned how the marketplace model really works. The retailer sent the wrong color, so I opened a ticket through the Help Centre. Replies took a couple of days between messages, not instant chat. They approved the return and processed my refund only after the parcel showed as delivered on their end. It was resolved, just slower than I hoped. If you want same-day answers, you might get antsy. If you can wait a beat, the refund does land eventually.