Apple has announced that DND bug will fix itself after January 7th. Apple also acknowledged that a bug made the Do Not Disturb feature on iOS devices inactive, on the New Year's day.
Apple added Do Not Disturb in iOS 6, which is a feature that allows you to block notifications from lighting up or making noise on your device. Do Not Disturb includes a scheduling feature which allows one to automatically shut this mode off at a time you want.
Apple Published a report on its official website which said,"Do Not Disturb scheduling feature will resume normal functionality after January 7, 2013. Before this date, you should manually turn the Do Not Disturb feature on or off." Apple is working on the fix of this bug, so that it never creates a problem in the future.
This bug caused the DND feature unable to shut off as scheduled, and left this feature active until one switched off it manually. some reports even claimed that a reboot was being compulsory before their device acknowledged these changes made.