How can I pump more milk?


I’m pumping multiple times a day and get somewhere between 1-2oz each time, how can I increase this? I’m only 9 days postpartum so trying not to get too discouraged but these small amounts really only top baby up between her formula feeds which are 4oz each. When trying to breastfeed she would feed for 2 hours and still want a bottle after so I decided to start pumping to try and get a better idea of how much she’s getting