Beaks constantly grow, like fingernails and rodent teeth.
You may notice flaking on the outside, thats pretty normal for hand reared birds. They don't have adult birds to teach them where and what to rub their beak on to keep it groomed (on the outside). If you notice your bird rubbing their outer beak on a certain perch, you may try replacing that perch with a rough or sandy one.
The bottom beak may also chip or loose chunks, because the beak does not wear down quickly enough. It will often even out after a few days (if say one side broke off but the other didnt). This is seen in captive birds since they don't forage through tough objects or may not get as much chewing as needed to keep it short.
When their beaks are looking long on the bottom, my girls get extra shell on almonds. When their outside beak is rough, I gently scratch off any loose pieces and give them papaya (which they always beak rub on perchs after).