Car battery dies and its new been recharged & definitely no the alternator on 2002 Dodge Stratus

My battery was bought 9/12 and well it failed since then, the battery would die, I recharged it and through time thought it could be the alternator but according to the Auto Zone machines its not the battery or the alternator... What could it be???

2 answers
if it is charging ok then charge and load test battery if it drops below 9.6v then the battery is no good
AGREE WITH GOODGUY OR YOU MAY HAVE A VOLTAGE DRAW