Do Not Disturb!!! Totally stopped disturbing me!!!!

For last two day, the Do Not Disturb feature in Schedule Mode is malfunctioning on my iPhone5 with iOS 6.0.2 (10A551). Whent the Schedule Time feature is turned on; whatever the scheduled time is, it goes into Do Not Disturb mode immidiately; it remains in that mode all the time!!!! and not get back to the normal mode after the schedule time!!!!

Any one faced the same or heard about this problem? Any solution?