Barely make enough milk for my baby and she won’t take a bottle

She’s nursing all day because she can’t get enough. I eat oatmeal, I drink a shit ton of water, I’ve tried lactation cookies, power pumping.. we were supplementing formula but now she won’t even take her bottle. So now she will get super hungry and cry and cry and cry. I don’t know what the fuck to do. What am I gonna do when her milk needs increase? She’s almost 3 months so she still doesn’t need a whole bunch but what about in a couple months? God it’s so frustrating