Finally heard back from Changelly and it looks like they are just keeping the money. As some have mentioned very scammy. But it is spelled out in their terms of use so I guess lesson learned read all that thoroughly before using a service and understand, too, how your wallet will be sending the coins.
Try again with another ticket from the support team, sometimes the support team responds differently, some are helpful, but try to contact them with more than one ticket.
if you do not find an answer try to ask them on reddit. It is true that it is mentioned in the terms of use but at least force them to put a warning to avoid such problems in the future, and stop using Changelly.