How to get a stash?

I’ve been exclusive pumping for a while but I feel like I can’t keep up. I’m only making enough to last for 1 or 2 feedings. So I have enough to make it through the day but not enough to store some away in the freezer. Any advice on how I can get enough for my baby to eat and enough to store?

I pump every 2-3 hours during the day and once around 1-2 am at night.