Pumping for twins.

Im only making enough to feed them for their next feeding! 😭 I want to be able to make more. I started pumping every hour. Idk how to increase my supply. I’ve tried power pumping. Any suggestions? One of my babies got NEC and they are about to go over 2 oz a feeding and I know with breast feeding your boobs adjust the supply based on them. How does it work with pumping?