Sounds like your hands aren't properly aligned. Set to the watch until it's close as you can get it to when the date flips, then stop it. Remove the hands, and then reset them at the 12 o'clock position.
When i first got it, it changed normally at 12, and the date started to flip at 11pm. But last night i noticed that it wasnt flipping, so i adjusted the time and it flipped at 3.
Sounds like your hands aren't properly aligned. Set to the watch until it's close as you can get it to when the date flips, then stop it. Remove the hands, and then reset them at the 12 o'clock position.