Change birthday on facebook?

okay so one time i accidentally set my bday to june 17 1995, and my real bday is july 17 1996 and i would like to know ow i can change it. every time i try it wont let me... like the year is locked in and you cant change it. so i atleast tried to change june to july and it said it couldnt change that either.. but at the bottom of the page where you hit "save changes", there was this link to report it and you are supposed to click that and go change it + add reason why you are changing it and it let me change it to the normal thing, and said "saved successfully" then i went to my profile to make sure it worked, and it said june 17 1995 again! so i cant figure out the problem.. help please!..