Tips for milk production?

Hi mamas! Does anyone have any tips, products, or remedies that they know of that helps milk production? The first week and a half I was producing up to 6 ounces per pumping session every two hours (I pump and bottle feed because she falls asleep latched on) now the past week and a half I’ve only been able to produce 2-3 ounces per session. She’s coming up on three weeks and that’s barely enough for one bottle let alone being able to build a supply. I’ve tried milkmakers lactation cookies, upsring drink, and pink stork tea (and of course staying hydrated with water) None of which I feel has made a difference. I really don’t want to give her formula it upsets her tummy. Any advice??