Battery Light Flashing on 2004 Honda Element

I just bought a 2004 element. Had it for a month with no problems. Last week the check battery light started flashing. I took it to AutoZone to have it schecked and battery, alternator, all turned out good. I took it to the dealership and they replaced the alternator. The next day the check battery light is back on. Any idea's?

Asked by for the 2004 Honda Element
they replaced alternator, you should replace battery if over two years.