Decrease supply

I’m almost 8 weeks pp and unfortunately our daughter doesn’t agree with breastmilk. I’ve altered my diet and tried different types of bottles (she wouldn’t latch from the start). We are giving formula only a try for a week to see if that works better for her. I want to continue pumping (then freezing) just in case but I have such a big supply. I typically pump 5-6 times a day and average 50 oz. I cut a session out and ended up pumping more than 50 oz in 4 sessions! How can I decrease my supply without drying out completely?

Also- if she ends up on formula only, is there somewhere I can easily donate breastmilk? I have over 300 oz in my freezer as of now.