sounds like you bought old ones that were getting ready to die
i throw out brown/black ones mostly if i buy colored
you might not have kept them cold enough while you had them on you
i have had a bunch for over a month and none have changed/died and i use insulated bait pucks and they go straight into the fridge when i get home and i try to keep them the same temp all of the time
my fridge is 38 degrees. always in the same container