2nd phone broken and unrepairble

Apple Doctor Maitland - 2nd phone is 1.5 months broken and unrepaired by Apple Doctor Maitaland. On both occasions my phones were fully operational, only the screens needed replacing. On collection of both phones, I was told that the phones, were not working anymore!!! At no point during the day did they contact me, explained that the phones after removing and replacing the screens no longer work??! The refused to take responsibility even after I specifically made note to them that this is the second time. Not acceptable that the technicians were not available, nor the manager!