Conventional braces, which use small elastic ties (ligatures) to hold the archwire in the brackets, are adjusted by the orthodontist every month. At this appointment the elastic ties are taken off and sometimes the archwire is changed. New elastic ties are put on, because the old ones have stretched from being in the mouth and plaque has built up on them. If a patient can't see their orthodontist within the month, the elastic ties will stay in place, but if they aren't changed for several months they may start to break and fall off.
This answer is for general information. Your own case needs an examination by an orthodontist.