I have very difficulty to produce breast milk. I produce only 4 oz a day. Almost give up, can anyone give me advice on how to increase quantity?

Im working mommy, pumping at work only 3oz per sessions.. 3oz x 3 sessi = 9oz..back from work focus direct breastfeed, no pumping.. Alhamdulillah, enough for my child,. Now 1year3months..goodluck mommy.. Enjoy ur breastfeeding journy.. Dont stress, drink a lot of water.. Keep breastfeed baby, more demand, more supply.. 😊