First timer having some trouble with fermenting

[u/dwiggs81]

I've read on a lot of forums that Ziegler's cider is the best for those of us in large cities where access to fresh cider is hard. I added a pound of brown sugar into 2 gallons of Ziegler's cider, then let a full sachet of yeast activate in warm sugar and honey water until it was nice and bubbly, then split it into 2- 1 gallon carboys. For the first day things looked happy, very bubbly, but the next day zero bubbles and no movement . After 2 full days and no new activity I activated another full sachet and let it bubble for 4 hours before adding it to the carboys. Again, nice activity at first but the next day nothing. Is there something I'm doing wrong?