All auctions in DUMO operate based on the Global Positing System (GPS) time. If the local clock/time for your local device (especially a mobile device) is set differently from the GPS time, there is a possibility that the auction may have appeared to have ended earlier or later for you.
We recommend that you align the local time/clock of your device with the GPS time to obtain the accurate time auction time. As always, the Auction start & end time set in our server will always be final to ensure fairness to all users globally.
You may refer to the GPS time here: https://time.is