Coindesk is reporting 16 names were lost due to a glitch in a recent .ETH domain auction. And, because its a distributed environment, there is no way to undo or fix the transaction.
OpenSea, which was running the auction, is trying to fix the problem, at a cost. They are offering a 25% reward for the return. (See link below) My guess is its money well spent for the publicity it will bring from people asking what are .ETH names anyway.
Unless they give the name to the winning bidder, I also predict it will sell for 2-3x the prior winning bid.