Intimissimi Online Item Wasn't Tagged As Non-returnable Yet They Refuse to Take It Back

I ordered a bodysuit from the Intimissimi website. I checked the return conditions under the product and didn't see any mention of 'non-returnable.' Later, I found the product left at my doorstep. Thinking I wouldn't wear them, I wanted to return the package without opening it. However, my return took a long time. When I called customer service to ask why, they said it couldn't be returned because it was a bodysuit with snaps. Despite explaining that I hadn't opened the package, I couldn't convey the situation. They said the products would be sent back to me, but despite days passing, there was no progress. When I called customer service again, I found out the products were lost. Currently, I haven't received my money back or my products. I paid ₺3400 for an unopened package. Despite multiple calls, no solution has been found, and I don't know what to do.