I might have to give up breast feeding. my supply isn't meeting her demand. I used to have a nice…

I might have to give up breast feeding. my supply isn't meeting her demand. I used to have a nice stash saved in my fridge but it's dwindled down now. I would love to breast feed her on demand but I have to use a shield and by the time I find the shield and put it on she's way too fussy and agitated so she won't latch....