Sudden milk supply decrease

Mommas, I need help!!

Out of nowhere my milk supply dropped significantly. I pump during the day at work, and breastfeed at night. I’m not sure why, but I’m thinking its hormones related (hoping) and that it picks back up. I normally pump 4-7oz each side, per pumping session, now I’m lucky to get 4oz both sides combined.

Is there anything I can do to quickly boost my supply. I’ve been chugging water and oatmeal. I don’t have access to a lot of supplements where I live, and to order them wouldn’t get here fast enough.