The auctioneer has made a mistake by announcing you the winner, caused by the last minute offer. Regardless of it, the auction never stops or pauses once started, parameters are set and unchangeable from start to finish. Announcing the extended 15 minutes is optional, it's a forum auction so if it stopped being advertised in-game, that's just less exposure.

 

The rules are known by every party involved. It wasn't poorly handled since it wasn't traded to you. An offer was submitted within the deadline, and bidders have access to that time. What we recommend is to keep on bidding regardless of comments that is over, proceed as normal. This way when a Trade Moderator reviews the auction, bidders aren't as affected by the confusion.

 

Apologies for the inconvenience but the outcome is final. Let me know if you have any other question. Take care.

Sorry for any inconvenience caused @Mingrenpro @Seoulmate. Timing was down to the seconds/minutes so I couldn't really tell. I did not want things to become more complicated so the only reasonable way to fix this is by involving a trade moderator.

The winner for this auction is @Seoulmate with highest offer of 4.5m. 
Due to a bug, I'm also unable to trade the water shuriken. In the announcement, it said that the cosmetics are tradeable. I've reported the bug and waiting for further confirmation on this matter. Again, sorry for any inconvenience caused.

successfully sold water shuriken