6 month supply decrease

I have hit 6 months breastfeeding.. However I am struggling to keep up with my (no so little) guy. I am a working momma so I am a combo of breastfeeding and breastmilk bottles. When I am with him, no bottles. Bottles only go to daycare! Ivan pumping as much as I can at work!! I pump on the way to and from work as well. However getting what he needs at daycare is a struggle! Any tips on how I can boost my supply! I am dipping a lot into my frozen stuff and am afraid in a month or two I won't have any left and then I won't b able to keep up with breastmilk!